Had the overheating issue while on vacation in Florida. Had the radiator fan replaced. Got home, and the fan started acting up again. I stumbled across your video and found out that the 40 fuse was popped. Replaced. No issues as of yet. Thank you tremendously!
Just wanted to thank you!!! My 2014 sonic was blowing cold air when I was moving but when I stopped or was idle, it was warm, hot air and the other day the dash icon for overheating went off! Thought it needed coolant or a recharge, but then I saw this video, and I finally got the chance to check the fuse, and sure enough it had blown... Went to Advance Auto, paid about $6 bucks and all is well... Thanks again!!!
Thank you so much for this video Russel! My 2018 Chevy Sonic (sedan) was not blowing heat. I was researching the topic. I checked the coolant level (it was normal), no leaks from hoses, I was researching replacing the thermostat on youtube and found this video of yours! I went straight to the autoparts store for that 40 amp, low profile J box fuse (less than $5). That white plastic tweezer in the fuse box us the fuse puller. It did not work for the J box size although. Once I removed the old one, I replaced it with the new fuse as you did. Heater came right back on!!! Man you saved me easy $300 plus. Thank you!!!
Just wanted to say thanks! My wifes Sonic was only blowing cold air when she was moving but when stopped, was blowing hot air and sometimes overheating and this turned out to be the problem. Specifically the smaller 40 fuse. Thanks again man!
A scantool or Torque app should be able to verify proper operation of the coolant temp sensor, without having to the place the coolant sensor itself. Always test fuses and relays first before replacing more expensive parts.
You're the man. I would have had to put the car in the shop in the morning. Turned out to be that 40 amp fan fuse. Just swapped it with the blower 40 amp fuse (just to verify) and the cooling fan started working. $5 for a fuse at Autozone and were all good. Thanks
Fuses blow for a reason people. It’s usually means it’s time for a fan motor or their might be an intermittent short. Fuses are circuit protection. They do not just go for the hell of it.
Just wanted to say thank you for making this video! I have a 2012 Chevy Sonic and we had this exact issue happen to us. You were spot on with the fuse. That fixed it! I will say we noticed our AC stop working a day before we started getting the overheating issue. The AC would only blow hot air when driving slowly or idling and then when we got to high speeds, it would blow cool air. So if you experience this along with overheating, it's probably the fuse. Thank you again!
What fuse size did you use? 30 or 40? Because my car is doing the same thing and the AC is doing the same thing and I change the thermostat but it’s still doing it so it has to be the fuse. And what fuse are you did you change exactly?
THANK YOU SO MUCH! My girlfriend's fan was not turning on, so immediately I thought it was the fan motor (as was the case with my old cavalier). 3 minutes after watching this video, I found that it was in fact the same fuse you referred to. You just saved us some money, thanks a bunch!
Bro this was a life saver ....made it so I was able to see my kids for the first time in months ...not a mechanic at all but you made it possible for me to fix . Thank you !!!
@6:30 You saved me so much more trouble. I've replaced the fan assembly twice in the last year and I knew that couldn't be right. It was the damn fuse.
Deathbound I'm glad it helped you.. it's funny it took several days to figure out all I did.. even the service shops didn't have all of the info... again... glad it helped
Thanks for this video!! It just helped me out big time! Car was over heating in hot weather, couldn’t figured it out until you showed the fuses. Rookie mistake on my part.
PLEASE NOTE: THESE CRUZE/SONIC ENGINES RUN AT 227 DEGREES. DEXCOOL 50/50 MIX BOILS AT 240 DEGREES. This is not enough margin to prevent boiling as the coolant heat soaks after shut down. I fixed my boiling problem by simply draining coolant and going with straight undiluted dexcool. Now I have boiling protection up to 28 Degrees. no more boiling at all. These cruze/sonic engines run much hotter than we are all used to, and thus require undiluted dexcool, not a 50 50 mix. These engines run this hot to meet emission standards. Thank Big Brother for this.
DON'T BELIEVE EVERYTHING YOU READ ON THE INTERNET (like the above). Yes, adding antifreeze will raise the boiling temperature, but the big increase in the boiling temperature comes from pressurizing the system! Pure water at 15psi boils at 250 degrees whereas a 50/50 mix boils at 264 degrees. The is plenty. If one has a boiling problem, then it is likely due to air in the system which was not properly burped out. My guess is that replacing the coolant with undiluted coolant worked because in the process the air was burped out and did not work because of the pure mix. Using pure coolant in your car is actually bad, read about it on the internet ;-).
great video, my daughters Sonic overheated due to a crack on the thermostat housing. At first I thought it was a bad hose, the crack was under the hose at the upper radiator connection. 32$ part at auto zone. So far so good. your video helped!!!
Thank you very much. You saved me soo much money. I went through everything you did. I decided to swap the 40A fuse with another 40A fuse , and it was the fuse. It is so difficult to look at the fuse and tell if it is bad. In the past year I replaced the thermosat housing unit, and I checked all the other items you suggested. I will buy a new fuse in the morning, and hope the fan does not blow the new fuse.
Thank you so much for this simple explanation. I had replaced the thermostat and housing and fan wouldn't work. Had checked the fuses and swapped relays and didn't fix it. Missed those fuses on the backside of the lid.
You really can't imagine how long I've been searching for this video. Very very useful for my Chevy Sonic (in Italy its official name is Chevrolet Aveo II serie). 🙏 Thanks
Great video- saved me a lot of time and money. Thanks. I thought it was my thermostat, even after looking at the fuse. It seemed ok. But I used my phone to take a picture and zoomed in to see the break. Put in the replacement fuse and the fan came right on. Thanks
Trishelle Belisle so my issue was the 40 amp fuse. It doesn’t sound like that’s the problem you’re having, not if they told you they want $2,000 to fix it. I’m not too sure about the other solutions. I just bought a new fuse from a GM supplier and popped it in myself.
i’m sending this to my mechanic in the AM. i have spent over 3,000 grand on this issue over the past few years. i hit a huge puddle a few years back and it began all my car issues. my car went back to one shop three different times for the exact same issue with my temperature gauge. everything was fixed and then i started having issues again. my car went back to the shop like four different times, the last time they said they fixed the issue. i was moving to kentucky and they kept reassuring me it was fixed. i’m so glad i towed my car because it would have overheated during my move because i was stuck in traffic. i didn’t realize the issue wasn’t fixed until i was on my way to tennesse and my car started to overheat in a traffic jam. i contacted a highly rated shop, brought my car spent 300 dollars two days later i felt my air stop blowing cold air at a red light and my light started to flash. i’m so frustrated!!!! literally no one can fix this issue!!! hopefully they can fix it by watching this video and not cost me anymore more money!!! thank you!!
Great info! Thank you! I also have a 2013 Sonic LT 1.8 and just recently got the high temp light. I had assumed changing my leaky radiator would fix this, but I'll definitely be checking these other areas to make sure I've covered all bases! The Chevy dealer wanted to charge me $1300 just to change the radiator!!!
Thanks for sharing your experience, you just saved me a lot of troubleshoot time and very likely a lot of money changing pieces trying to find the root cause of the issue. Really appreciated. Saludos from Monterrey, Mexico!
This is the most helpful video I've seen. I bought a used chevy sonic about 3 weeks ago with 96,000 miles and for $5,000. It was a great deal but as I'm close to my house there's a big line eith cars so I had to stop and my car threw an overheating signal. It had the 4 problems you described ( I finished fixing it today) First I checked my fuse box and noticed the fuse you mentioned was blown but it was my radiator fan that was broke since it kept blowing them up. So I changed my radiator fan and fuse and it was good but later it started to leak coolant and it was the thermostat so I had to replace the thermostat and the thermostat housing since it was cracked . The entire cost of my repair ended up being $140. Once again thanks for this awesome video. It helped a ton.
Favio Escalon I'm glad my video helped you. It seems the Sonic has this issue a lot.. most shops seperate repair labor from diagnostic labor.. it's great to see people using this vs paying for expensive tests
Awsome, I use youtube videos all the time to get different ideas and information on many things from installing shower tile to auto repairs of all kinds and this is the most informative and detailed video that I have seen in the five years I have been using CZcams. THANKS FOR YOUR EFFORTS AND SHARING!!!
First of all, i want to thank you, for the time you took to make this video, this help me with my check engine light, P2181 Cooling System Performance. I did the fuse change and the check engine light came off. Thanks.
It's funny... you wouldn't think a 40A fuse would blow, but mine did. I was waiting for a kids meal at Wendy's and the dreaded hi-temp light and annoying chime came on. Thank you for the good troubleshooting path video. One thing.. in my fuse block 6 and 7 (30 and 40 amp) are switched. I checked the listing on the lid and they were installed correctly. Just surprised that they would be changed.
Great info.. thanks for posting. I'm glad this video helped.. this car seems that there is so much more than just the thermostat can go wrong... and the shops (I visited) didnt seem to know anything about the electrical issues.. .only to replace the thermostat..
I already replaced the all in one cheap plastic housing that cracked from the factory... It came wth the thermostat and temp sensor preloaded. Then replacement had better reinforced mounting, but still plastic against metal can cause issues. Of course after I changed the 40A fuse the alarm chime wouldn't stop until I disconnected the battery. But all seems to be working, for now. Thanks again.
Just recently October 2021 had the same problem with my 2014 Sonic and it ended up being the exact same fuse discussed in this video thanks for sharing
Thanks for the Video! I was about to start taking apart the Thermostat right before i seen this. This is a goofy made motor lol i had to recently change the PCV valve which was told is also a common issue and it makes sense why it fails
Very helpful video. I had a slightly different issue which is my radiator cooling fan was only working on the high speed setting or not at all. Took the car to a specialty AC/radiator place and they said significant corrosion on the fan motor had disabled the low and medium settings. Replacement of the radiator fan came to $224 including labor (summer 2020) which was significantly lower than I'd expected. A possible cause seemed to have been a very slow leak of coolant from the radiator overflow bottle, which was cracked. I had that replaced later....one of those rare cases where the Dorman component is clearly better than the GM one. I agree, though, fuse and relay stuff is more common than what I had.
Great video, I eliminated fuses, relays and the temp switch. It was the Fan resistor attached to the shroud, The resistor is soldered on of course and attached to shroud, none available separately, dorman (621-071) makes a complete shroud with new fan and resistor for about $165 at Autozone now she cools like a champ ! 2014 Sonic LT 1.8L
Thank you so much for your video I have recently gotten a thermostat replaced which needed to be replaced and just today the fans. Kicking on and I noticed that the car was overheating and the temperature light came on which is very annoying because it Heats very loudly so I remembered your video and went and got the fuse and I fixed it so thank you very much
Russ thanks for making this video, it helped me tremendously!! I had my temp light come on the first time and checked the coolant reservoir. It was empty. I started looking for leaks and had none. I added coolant and thought the issue was fixed. Today it comes on again, I do a google search and your video was the first to pop up. I checked the fuse and made the switch as you did and it solved the issue. You have saved me a lot of money sir, much appreciated and God Bless you sir!!
Hi Russ, your video was informative, I found the problem was the temp coolant sensor. It seems to be giving a signal that the car is overheating, thereby making the fan run continuously and temperature light constantly buzzing. Hope my experience will help someone if they ever have the same or similar problem.
Glad to hear it helped. I have no idea why that fuse blows, but it's a great idea to keep a spare with you. There are a few unused fuses . And relays in that box that you could use in a pinch. Thanks for the note
That “sensor” is actually part of the heater control circuit-it’s basically a way of electronically controlling the mechanical thermostat. The coolant temp sensor is located closer to the firewall on these cars. Good call on checking the fuses/relays and fan! My wife’s Sonic is acting up and I haven’t looked at those yet.
@@keylay9453 the mechanical portion of the thermostat is temp dependent, so it will stay open on a hot engine, closed when the engine cools to a certain temp. The heater control circuit allows the computer to have more fine control of that open/close temp for better fuel efficiency and emissions related things
Thanks a bunch! It was the 40 fuse for me. The fuse looked fine but it did look different than the others. Tested with the 30 fuse and it worked. 2012 LS 90k miles. Ac was blowing hot air then Temp sensor came on. Radiatior fan was not turning on.
Thanks for this video. I don’t have that problem on my Sonic, but I just happened to be scrolling through random videos on CZcams and this one caught my attention. So I’ve gone ahead and saved it in case one day I experience this issue. I have a Sonic Repair video folder I keep videos like this in. Thank you 😉👍🏼🔧
Thanks for the vid man helped me alot with fixing my fan I realized it wasn't working because the heat warning came on but was just a blown fan fuse you saved me alot of money most likely appericate it!!!
Chevy don't add a temp, oil pressure and battery gauge in sonic. Making those car into money making scams. My sonic only had 108k and don't warn me it was heating up and low coolant. It ran fine but as I checked all my hoses they bubbled up causing leaks, then my fan was always on almost melting the connection to fan. I checked my thermostat, all the seal where cooked but no warning for low coolant or codes' I mean nothing, now it showing signs of bad head gasket' little milky in coolant' I was like wtf chevy car from hell. Should of got a toyota, nissan or ford' I focked up
chem dog you are so right my girlfriends car had the same thing now its a bad headgasket the echaust started smoking so bad it filled the whole block with smoke it was a nightmare now i have to deal with taking the bullshit car apart to replace one headgasket cause we were curious on why we had to keep adding water to it after all of that it never turned on the temp light on or the low coolant light it sucks this car just sucks in general
Yeah tell me about it, I'm 4000$ in debt from engine failure when it NEVER warned me of a thing and I still owe 7000$ on the car. Fuck Chevy for this, FUCK Chevy for this
@Al Dunn You are right about questioning why the fuse blew. Just replacing that fuse and assuming the fused failed because of "old age" is a BIG mistake. Fuses fail because of excessive current flow, not just fatigue. The next step, once the fans are working, is to throw a clamp meter on the fan wires to determine if the current flow is within normal limits.
Mine too. My Sonic is a little over 60,000. Im having the overheat issue right now. My mechanic was SURE he fixed the problem. Were gonna watch this video in hopes we can find the issue. Im not doing American cars after this. Honda or Toyota for now on!!!
Thanks!, That darn 40A fuse was blown and as you stated it did not look blown. I had to remove the fuse and plastic cover to actually see that it was blown. In my case the fan was bad too. To test fan, unplug and connect the 1st spade to Ground, and the 2nd spade to +12V, then move the +12V to the 3rd spade. Both times the fan should come on. Looking at the fan wire socket there are 1, 2, 3 spades with 1 being on the brown wire side and 3 on the red wire side.
There’s a low speed and high speed relay for the radiator fan, and fuses for each, hence the 30A (low) and 40A (high) fuses. The radiator fan plug has three terminals, where the middle is the ground and the outside two are-you guessed it-the low and high speed power inputs. The low speed power terminal actually has a resistor in series (to create the low speed). You can check the fan’s low-ground and high-ground circuits with a multimeter to rule it out.
Yep! My fuse was blown! I also double checked the coil of the relay, and compared it to the other identical relays. Noticed that the resistance of the coil was about 20% higher on the coil of the fan relay. That leads me to believe that the coil is going out, causing the fuse to blow. Changed both for about $10!
almost 4.5 years later I have been screwing around on my wifes sonic, and totally forgot start cheap work your way up. (she usually takes hers to the shop) and since my daily is way easier to work on (motorcycle) its one of two things for me. I keep forgetting to look for fuses and relays. Thank you!
Thanks for this bud!! My '12 sonic is my daily driver to keep my miles low on my pickup and it just started overheating on very hot days, but cool days it was fine. Long story short the mechanic said $325 to replace the fan shroud but it was just a blown relay!! Fan worked instantly!!👍👍👍👍
Will be looking at same issue on Thursday. Fan doesn't come on. Fixed the coolant leak today, drove around and that overheat symbol cane up then realized fans not coming on. Great video. Thanks
Thank you sir, nice video. I Chevy Sonic 2012 1.6L. My fan is working good (when turning on AC and other times), but my temp light sensor never appeared before, even when I had major problems of water leak or oil mix in coolant or so. However, check engine light was showing sometimes and some error codes (like coil issue), but never saw the temp sensor light during 7 years. Is that normal? And should it show in the computer test as an error code if it was faulty?
@@russelmccombs honestly thank you a hundred times bc i had to mechanic places (one was a gm dealership) wasting my money telling me they dont know and replacing parts tht didnt need to be replaced 🤦🏼♀️ Your video is truly saving cars n wallets 🚗💙
The issue with sonic's in general have engine cooling system failure. If your fan keep kicking on, it has heat problems. I found trapped air leaking in my ratiator system last week, in the same time destroys all my hoses, ratiator, thermostat, seals, oil cooler without warning' I mean no codes or anything. Also Chevy position the hoses lower then the cylinder head and Same goes for the reservoir and sencor's, why?. Over all chevy did Shity engineering on those cars.
I replaced the thermostat that came with the new sensor on a 2016 1.8 I couldn't get that plug to plug back into the sensor. After many attempts trying the connector both ways, my granddaughter got it to plug in. I took that plug off and I'm sure it's on wrong. The warning light went out , but the fan doesn't come on when the AC is on . I'm going to apply 12 volts directly to the fan as you suggested. But what do you think could that thing being plugged in backwards make the fan not work but still shut the sensor warning light off.oh the sensor has little square part sticking out on one side. The other side also has a little plastic part sticking out but it is beveled not perfectly square on that side. that's the side I think releases when you press the tab. the release tab is currently pointed towards the square one which is facing towards the engine block.
5 Stars and golden jelly beans for you...sure enough it was the fuse 40 that was shot...$ 5.75 fixed the problem....a bad day for my mechanics bank account..
We are having the fuse blowing issue with my girlfriends 2013 Sonic 1.8 as I type this. I thought maybe it was a fluke that it blew the 40amp fuse the first time. So far, I have checked the cooling fan, it spins freely, no wobble or roughness in the bearings inside it. I checked the wiring, cleaned connections with CRC electronics cleaner, there are no melted wires, no marks or chaffing on any of the wires coating. There are no fault codes. In the past, this car has already had 2 thermostat changes, new antifreeze both times, Redline Water Wetter put in the second time to try to stop/slow down the corrosion that these things make in their cooling systems that prematurely stick thermostats open or closed, which causes the cheaply made thermostat to kick the, High current flow detected code. But back to the fuse blowing. I have swapped the small dark gray 8430 AC compressor/cooling fan on relay with another. Thanks to your video that shows the proper location for the Cooling fan/ac compressor on relay. But it blew the fuse again. We have let this car sit for two hours running in my garage with the ac system running on the high setting, ac compressor cycles like normal, the cooling fan kicks on and off into high like normal, it blows ice cold air, but take it out on a road and drive it or get stuck in traffic and it blows the fuse again, which causes the ac to stop working and it flashes the overheat light on. I have since ordered the two larger lighter gray relays that control the low speed and high speed sides of the fan. They are the relays in your video with the 120002967 part number. They are the two larger square relays below the 40 and 30amp fan fuses. One is low speed fan relay, the other is the high. Top relay right under the 40amp fan fuse I believe is the high speed fan relay. The 120002967 number is obsolete and is replaced by GM part number 13500118, these relays are a darker color. I have yet to replace them because of our sometimes conflicting schedules, but will comment again if it cures the problem. But just to add something that I seen and read on RepairPal. 2008 and up Malibu's have the high speed cooling fan fuse issue as well, and GM's so-called "fix" is to put a 10amp larger fuse in and replace the wires running to the cooling fan with larger wires.
Thanks for the great info. No one has been able to answer why the fuse blows in the first place... it does seem a model glitch... and maybe the Malibu solution you found might work here too. It's a crazy car for sure. Let us know
Russ M You're welcome. I was able to replace the relays a day after I commented on your video. So far, The Sonic seems to have stopped blowing the 40amp cooling fan fuse. I'm not 100% sure which relay may have been at fault, so I replaced both just for peace of mind and because the car has just over 100k on it. But if it helps anyone else who has a Sonic that keeps blowing the 40amp fuse and everything else checks out ok and is working properly. They may need to replace the low and high side cooling fan relays. If the relay/relays start to fail and will not hold contact to supply steady continuous power to the cooling fan, the constant kicking on and off may be causing enough of a power surge or if the relay is some how shorting out inside, it will blow the fuse. From what I gather, the Sonic 1.8 needs both the low and high side relay circuits to engage, cycle, and run/operate the cooling fan speed/speeds as needed by the cars cooling requirements. So its possible if one of these relays stops working properly, it could cause a excessive amp load on the high side fuse causing it to blow. If I understood the cooling circuit and wiring diagram correctly, the fan comes on on the low side first and immediately cycles to high right after , so instead of it going from fan off to fan on high, it has a very short two stage/step cycle to engage the fan on to high speed so there is no excessive amp load on the high side fuse. Low side is a 30amp, and the high side is only a 40amp, so its understandable why it transitions from low into high this way. Its easier on the fuse. I also believe that is why the 1.8 Sonic has the big resistor coil hide in the upper part of the electric cooling fan shroud. Its another attempt to try to ease/lessen the voltage and amp loads on the cooling circuit of these cars. I have seen that the Sonic with the 1.4 turbo has low, med, and high speed fan relays, and I have not seen many problems reported with fuses blowing on the turbo cars. There may be less of a strain on the cooling fan circuit because they have low, med, and high cooling fan relays and the fan is able to cycle from low, med, and high as needed. But I don't believe I would want to just pop in a larger amp fuse like the Malibu "fix". Because even if the wire size to the fan is increased, the rest of the circuit has not been upgraded and may cause even bigger problems down the road.
@@russelmccombs Thought I would give you a update. Its been over a month after changing the high and low speed cooling fan relays. We have had weather in the 90's here on and off and the AC is still working. Hope my information may be of some help to anyone with a 1.8 Sonic that blows the 40amp fuse from time to time after the car starts getting high miles on it.
Does the fan run in 2 speeds? It’s hard to test it out, just switch a new fan in myself, the fan runs for a few seconds and then off when I turn on the AC, and back on after like 30 seconds. It’s going on and off like that….it’s snowing cold here, don’t know how long I should the idle until the engine is hot enough to kick off the fan
I have a 2012 Sonic (1.8) which overheated this past summer. I suspected it was the resistor for the fan which is right at the plug for it. With no actual proof of what it could be I simply cut the resistor off and wired a relay and a switch to the fan 0 $ as I had the relay and switch on hand. It's not the best situation because you have to be aware of when to turn on the switch. I am in Canada, so overheating season doesn't come often.
Thank you so much! My 2014 Sonic overheated while sitting in the drive-through and the next day I got an engine code from auto zone, they told me it was the temperature sensor going bad. I replaced that, and I was sitting in a parking lot idling with AC on and AC started blowing warm air and engine overheated. My engine overheated sitting in a lot and sitting in a drive-through, both times I was just sitting there so I checked the radiator fan and sure enough it wasn't blowing. Saw this video and replaced the 40A fuse and that did the trick. Now I just wonder why it blew to begin with. Thank you for posting!!!
You are awesome! I checked everything you did and was anticipating having to replace my mom's thermostat. Then you showed me the fuse and it was obviously blown. I also replaced it with the 30 amp to cover the trip to the parts store. Thank you so much! Just wondering, do you have any thoughts on why that fuse blew? A blown fuse is the result of a faulty circuit and I am suspicious that the fan may be the problem.
there have been over 140 cars with the same issue... (just replying to this video). I think it's an issue with the model.. I doubt its something "broken"... I think it's "how it is"... if anyone finds the reason for the fuse to blow, let us all know :)
Thanks you VERY much for doing this. 2015 Sonic with 33K miles. It started overheating in traffic with the alarm sounding. It was the 40 amp engine fan fuse. I swapped the interior fan 40 amp fuse to get me to the parts store. Have you continued to have any more problems with this fuse? I did buy a second fuse to keep in the glove box.
This is my son's car, I have asked him how it has been running and he says all good. There seems to be issues with this system in the Sonic (from my searches), keep an extra fuse is a great suggestion... we kept an extra too ;-). And you are welcome, the shops where my son is wanted $150 to even do a code pull and he's in a state that doesn't allow auto parts stores to do it for free, so I hopped this might help others... glad it helped you.
On the way home from work yesterday my 2015 sonic rs was fogging up the outside windshield, no light came on. But when i got home and went near the engine it was blistering hot. Hoping that was just a fluke... but will definitely check the 40 fuse... thanks for this video
Was there any coolant visible on hoses, engine, etc after the high temp indicator came on? Just checked one of the fuses on my son's and it does look like it's bad. However, I did see coolant around hoses
I did the thing you said about the j fuse I actually bought 1 40, and 30, then I did the ac turn, the fan unfortunately doesnt cycle on or off with ac on, now I will try try changing just the tstat, and not the housing unit,
Try running 12 Volt's to the fan the way he explains it. Fan should come on instantly, if it doesn't the fan is definitely bad regardless of any other fuses sensors switches whatever.
Thankss, i just got odb2 screen to check the cooling temp, my temp goes to 108 and then the fan kick, there is times that it goes to 111 , is this normalv
My keeps burning off coolant, i just check it every day and add water. And its buring oil. Seems like after i top off thr fluid its okay for a few days and they i have to redo it.
Had the overheating issue while on vacation in Florida. Had the radiator fan replaced. Got home, and the fan started acting up again. I stumbled across your video and found out that the 40 fuse was popped. Replaced. No issues as of yet. Thank you tremendously!
Great news! I'm glad my video helped
Just wanted to thank you!!! My 2014 sonic was blowing cold air when I was moving but when I stopped or was idle, it was warm, hot air and the other day the dash icon for overheating went off! Thought it needed coolant or a recharge, but then I saw this video, and I finally got the chance to check the fuse, and sure enough it had blown... Went to Advance Auto, paid about $6 bucks and all is well... Thanks again!!!
WOW!! Dealership said bad motor fan $989.00 to replace. Ended up being that 40 Amp fuse. You da man Russ.Thanks
I'm glad my video helped you.
Thank you so much for this video Russel! My 2018 Chevy Sonic (sedan) was not blowing heat. I was researching the topic. I checked the coolant level (it was normal), no leaks from hoses, I was researching replacing the thermostat on youtube and found this video of yours! I went straight to the autoparts store for that 40 amp, low profile J box fuse (less than $5). That white plastic tweezer in the fuse box us the fuse puller. It did not work for the J box size although. Once I removed the old one, I replaced it with the new fuse as you did. Heater came right back on!!! Man you saved me easy $300 plus. Thank you!!!
Just wanted to say thanks! My wifes Sonic was only blowing cold air when she was moving but when stopped, was blowing hot air and sometimes overheating and this turned out to be the problem. Specifically the smaller 40 fuse. Thanks again man!
Rick Dubois I'm glad it helped you. Thanks for the comment.
How much did it cost to fix it
@@Incrediblewash about 5 bucks for the fuse
@@russelmccombs Just solder a penny across that pesky fuse. I promise that 40A fuse will NEVER blow again. Sonics are easy to fix!!
A scantool or Torque app should be able to verify proper operation of the coolant temp sensor, without having to the place the coolant sensor itself.
Always test fuses and relays first before replacing more expensive parts.
my ears perked up as soon as you mentioned the island! such a small world!
haha, my son was stationed there and we were visiting. It's funny you caught that. I hope the video helped you.
You're the man. I would have had to put the car in the shop in the morning. Turned out to be that 40 amp fan fuse. Just swapped it with the blower 40 amp fuse (just to verify) and the cooling fan started working. $5 for a fuse at Autozone and were all good. Thanks
Mike R I'm glad this video helped you out. It's strange to see so many Sonics with the same issue. Thanks for the note
Fuses blow for a reason people. It’s usually means it’s time for a fan motor or their might be an intermittent short. Fuses are circuit protection. They do not just go for the hell of it.
Just wanted to say thank you for making this video! I have a 2012 Chevy Sonic and we had this exact issue happen to us. You were spot on with the fuse. That fixed it! I will say we noticed our AC stop working a day before we started getting the overheating issue. The AC would only blow hot air when driving slowly or idling and then when we got to high speeds, it would blow cool air. So if you experience this along with overheating, it's probably the fuse. Thank you again!
Glad it helped!
What fuse size did you use? 30 or 40? Because my car is doing the same thing and the AC is doing the same thing and I change the thermostat but it’s still doing it so it has to be the fuse. And what fuse are you did you change exactly?
THANK YOU SO MUCH! My girlfriend's fan was not turning on, so immediately I thought it was the fan motor (as was the case with my old cavalier). 3 minutes after watching this video, I found that it was in fact the same fuse you referred to. You just saved us some money, thanks a bunch!
that is great news! I'm glad it helped you!!
Can't thank you enough! You just saved me so much money and headache. It runs great now that I got fan going after changing out the 40 fuse.
Cameron Brewer That is great to hear! isn't it awesome when you can fix a seemingly big issue with a inexpensive part :-) glad my video helped you
Bro this was a life saver ....made it so I was able to see my kids for the first time in months ...not a mechanic at all but you made it possible for me to fix . Thank you !!!
I'm glad it helped you.
@6:30 You saved me so much more trouble. I've replaced the fan assembly twice in the last year and I knew that couldn't be right. It was the damn fuse.
Deathbound I'm glad it helped you.. it's funny it took several days to figure out all I did.. even the service shops didn't have all of the info... again... glad it helped
Thanks for this video!! It just helped me out big time! Car was over heating in hot weather, couldn’t figured it out until you showed the fuses. Rookie mistake on my part.
I'm glad it helped you... crazy car for sure
Great details you saved me a bunch of time with my daughters car. Went straight to the fuse and that was indeed the issue. Thank you for your video.
Great to hear! I'm glad my video helped.
PLEASE NOTE: THESE CRUZE/SONIC ENGINES RUN AT 227 DEGREES. DEXCOOL 50/50 MIX BOILS AT 240 DEGREES. This is not enough margin to prevent boiling as the coolant heat soaks after shut down. I fixed my boiling problem by simply draining coolant and going with straight undiluted dexcool. Now I have boiling protection up to 28 Degrees. no more boiling at all. These cruze/sonic engines run much hotter than we are all used to, and thus require undiluted dexcool, not a 50 50 mix.
These engines run this hot to meet emission standards. Thank Big Brother for this.
DON'T BELIEVE EVERYTHING YOU READ ON THE INTERNET (like the above). Yes, adding antifreeze will raise the boiling temperature, but the big increase in the boiling temperature comes from pressurizing the system! Pure water at 15psi boils at 250 degrees whereas a 50/50 mix boils at 264 degrees. The is plenty. If one has a boiling problem, then it is likely due to air in the system which was not properly burped out. My guess is that replacing the coolant with undiluted coolant worked because in the process the air was burped out and did not work because of the pure mix. Using pure coolant in your car is actually bad, read about it on the internet ;-).
great video, my daughters Sonic overheated due to a crack on the thermostat housing. At first I thought it was a bad hose, the crack was under the hose at the upper radiator connection. 32$ part at auto zone. So far so good. your video helped!!!
Anthony Vara I'm glad the video helped
Thank you very much. You saved me soo much money. I went through everything you did. I decided to swap the 40A fuse with another 40A fuse , and it was the fuse. It is so difficult to look at the fuse and tell if it is bad. In the past year I replaced the thermosat housing unit, and I checked all the other items you suggested. I will buy a new fuse in the morning, and hope the fan does not blow the new fuse.
They do keep blowing get rid of that car
Thank you so much for this simple explanation. I had replaced the thermostat and housing and fan wouldn't work. Had checked the fuses and swapped relays and didn't fix it. Missed those fuses on the backside of the lid.
Glad it helped you
You really can't imagine how long I've been searching for this video. Very very useful for my Chevy Sonic (in Italy its official name is Chevrolet Aveo II serie). 🙏 Thanks
I'm glad it helped. Thanks!
Great video- saved me a lot of time and money. Thanks. I thought it was my thermostat, even after looking at the fuse. It seemed ok. But I used my phone to take a picture and zoomed in to see the break. Put in the replacement fuse and the fan came right on. Thanks
I'm glad the video helped you
This video allowed me to handle this problem I had no idea how to fix in just a couple hours. I can’t thank you enough.
Glad to hear it helped you.
how were you about to figure it out?! I’m having the same issue and the dealer is trying to charge me $2000 to fix
Trishelle Belisle so my issue was the 40 amp fuse. It doesn’t sound like that’s the problem you’re having, not if they told you they want $2,000 to fix it. I’m not too sure about the other solutions. I just bought a new fuse from a GM supplier and popped it in myself.
i’m sending this to my mechanic in the AM.
i have spent over 3,000 grand on this issue over the past few years.
i hit a huge puddle a few years back and it began all my car issues. my car went back to one shop three different times for the exact same issue with my temperature gauge. everything was fixed and then i started having issues again. my car went back to the shop like four different times, the last time they said they fixed the issue. i was moving to kentucky and they kept reassuring me it was fixed. i’m so glad i towed my car because it would have overheated during my move because i was stuck in traffic. i didn’t realize the issue wasn’t fixed until i was on my way to tennesse and my car started to overheat in a traffic jam. i contacted a highly rated shop, brought my car spent 300 dollars two days later i felt my air stop blowing cold air at a red light and my light started to flash. i’m so frustrated!!!! literally no one can fix this issue!!! hopefully they can fix it by watching this video and not cost me anymore more money!!! thank you!!
good luck. I hope its this simple issue. let us know what they say.
Great info! Thank you! I also have a 2013 Sonic LT 1.8 and just recently got the high temp light. I had assumed changing my leaky radiator would fix this, but I'll definitely be checking these other areas to make sure I've covered all bases!
The Chevy dealer wanted to charge me $1300 just to change the radiator!!!
I'm glad this video gave you additional options to check. I hope it works out for you. Good luck.
6y
Thanks for sharing your experience, you just saved me a lot of troubleshoot time and very likely a lot of money changing pieces trying to find the root cause of the issue. Really appreciated. Saludos from Monterrey, Mexico!
Miguel Juarez That is great to hear! have a happy New year!
Thank you! You too!
Thank You for sharing your experience. It saved me time, effort and money.
This is the most helpful video I've seen. I bought a used chevy sonic about 3 weeks ago with 96,000 miles and for $5,000. It was a great deal but as I'm close to my house there's a big line eith cars so I had to stop and my car threw an overheating signal. It had the 4 problems you described ( I finished fixing it today) First I checked my fuse box and noticed the fuse you mentioned was blown but it was my radiator fan that was broke since it kept blowing them up. So I changed my radiator fan and fuse and it was good but later it started to leak coolant and it was the thermostat so I had to replace the thermostat and the thermostat housing since it was cracked . The entire cost of my repair ended up being $140. Once again thanks for this awesome video. It helped a ton.
Favio Escalon I'm glad my video helped you. It seems the Sonic has this issue a lot.. most shops seperate repair labor from diagnostic labor.. it's great to see people using this vs paying for expensive tests
From all the comments here about the faulty 40A fuse, Chevrolet should issue a "faulty fuse" recall!
agreed... 200+ comments ... 632 "thumps up"... to me means many folks have found this to be an issue.
Thanks so much for this video. It saved me a lot of time and headache on diagnosing why my 2015 chevy sonic was overheating.
I'm Glad it helped you
Thank, Russ! You saved me a few hours and $175. 40A fuse was the culprit in my case and first thing (easiest) I checked.
Glad to hear it helped you
Awsome, I use youtube videos all the time to get different ideas and information on many things from installing shower tile to auto repairs of all kinds and this is the most informative and detailed video that I have seen in the five years I have been using CZcams.
THANKS FOR YOUR EFFORTS AND SHARING!!!
First of all, i want to thank you, for the time you took to make this video, this help me with my check engine light, P2181 Cooling System Performance. I did the fuse change and the check engine light came off. Thanks.
It's funny... you wouldn't think a 40A fuse would blow, but mine did. I was waiting for a kids meal at Wendy's and the dreaded hi-temp light and annoying chime came on. Thank you for the good troubleshooting path video. One thing.. in my fuse block 6 and 7 (30 and 40 amp) are switched. I checked the listing on the lid and they were installed correctly. Just surprised that they would be changed.
Great info.. thanks for posting. I'm glad this video helped.. this car seems that there is so much more than just the thermostat can go wrong... and the shops (I visited) didnt seem to know anything about the electrical issues.. .only to replace the thermostat..
I already replaced the all in one cheap plastic housing that cracked from the factory... It came wth the thermostat and temp sensor preloaded. Then replacement had better reinforced mounting, but still plastic against metal can cause issues. Of course after I changed the 40A fuse the alarm chime wouldn't stop until I disconnected the battery. But all seems to be working, for now. Thanks again.
Boom! Fuse!! Thanks to this video it only took minutes to diagnose. That unused fuse verified it. Again, THANKS!!!👍👍👍👍
Great to hear, I'm glad it helped you
Thank you for the video. You saved my car and my bank account. From the average joes, we thank you for the video.
I'm glad it helped. It seems this car has some pretty "special" issues..
GREAT VIDEO DID THE JOB!! I like the explanation of your troubleshooting adventure. For me it was the last problem the 40amp fuse. Thanks again.
Thank you...and I'm glad it helped you. It's crazy how many people have had the same issue
Just recently October 2021 had the same problem with my 2014 Sonic and it ended up being the exact same fuse discussed in this video thanks for sharing
You're welcome, glad it helped
Thanks for the Video! I was about to start taking apart the Thermostat right before i seen this. This is a goofy made motor lol i had to recently change the PCV valve which was told is also a common issue and it makes sense why it fails
I'm glad the video helped you. pick up some extra fuses :)
Yes, i had the same issue and checked the fuse and it was blown. Thanks for posting this it was a huge help
Scott Chafe glad it help you!
Very helpful video. I had a slightly different issue which is my radiator cooling fan was only working on the high speed setting or not at all. Took the car to a specialty AC/radiator place and they said significant corrosion on the fan motor had disabled the low and medium settings. Replacement of the radiator fan came to $224 including labor (summer 2020) which was significantly lower than I'd expected. A possible cause seemed to have been a very slow leak of coolant from the radiator overflow bottle, which was cracked. I had that replaced later....one of those rare cases where the Dorman component is clearly better than the GM one. I agree, though, fuse and relay stuff is more common than what I had.
Thanks for the information
I bet they changed the block temperature sensor for $12 and didn't tell you.
Great video, I eliminated fuses, relays and the temp switch. It was the Fan resistor attached to the shroud, The resistor is soldered on of course and attached to shroud, none available separately, dorman (621-071) makes a complete shroud with new fan and resistor for about $165 at Autozone now she cools like a champ ! 2014 Sonic LT 1.8L
I'm glad it helped. Great info from you as well. Thanks!
Alright, man! Great vid. I have a Chevy sonic lt, same problem. Gonna go diagnose her. Thanks again!
Thank you so much for your video I have recently gotten a thermostat replaced which needed to be replaced and just today the fans. Kicking on and I noticed that the car was overheating and the temperature light came on which is very annoying because it Heats very loudly so I remembered your video and went and got the fuse and I fixed it so thank you very much
I'm glad it helped
Amazing! Thank you for sharing this with us. This was my exact problem.
Glad it helped.
Thank you for this video. Problem solved! I love these CZcams videos on how to fix your car yourself!
Signed,
She, Who Needs No Man!
😁💪
I'm glad the video helped you. It's a strange car. Glad you got it fixed
I'm glad it helped you
@Revenant
Touché
Signed,
She Who Admits She Needs A Man On Occasion 😉
Excellent...spot on, corrected the problem! Thank you!
Russ thanks for making this video, it helped me tremendously!! I had my temp light come on the first time and checked the coolant reservoir. It was empty. I started looking for leaks and had none. I added coolant and thought the issue was fixed. Today it comes on again, I do a google search and your video was the first to pop up. I checked the fuse and made the switch as you did and it solved the issue. You have saved me a lot of money sir, much appreciated and God Bless you sir!!
I'm glad it helped
Hi Russ, your video was informative, I found the problem was the temp coolant sensor. It seems to be giving a signal that the car is overheating, thereby making the fan run continuously and temperature light constantly buzzing. Hope my experience will help someone if they ever have the same or similar problem.
Yes, I've heard of that issue too. I'm glad you got it working
Thank you so much for sharing. You saved me a lot of time and $$$. The fuse was the issue! Thanks brother!
You're welcome!
THANK you so much for this video!! The fuse on my 2014 goes out on long trips and engine overheats so I have to keep extra fuses on hand for trips.
Glad to hear it helped. I have no idea why that fuse blows, but it's a great idea to keep a spare with you. There are a few unused fuses . And relays in that box that you could use in a pinch. Thanks for the note
you sir just saved me hundreds of dollars. Relay
John McGuinness -great to hear! I'm glad it helped you!
The coolant sensor is on the back side of the housing the sensor u showed is a heater for the thermostat
That “sensor” is actually part of the heater control circuit-it’s basically a way of electronically controlling the mechanical thermostat. The coolant temp sensor is located closer to the firewall on these cars.
Good call on checking the fuses/relays and fan! My wife’s Sonic is acting up and I haven’t looked at those yet.
Hey, I don't suppose you would know if the thermostat rests in the open position? Like if you turn the car off, do the thermostat open?
@@keylay9453 the mechanical portion of the thermostat is temp dependent, so it will stay open on a hot engine, closed when the engine cools to a certain temp. The heater control circuit allows the computer to have more fine control of that open/close temp for better fuel efficiency and emissions related things
Thanks a bunch! It was the 40 fuse for me. The fuse looked fine but it did look different than the others. Tested with the 30 fuse and it worked. 2012 LS 90k miles. Ac was blowing hot air then Temp sensor came on. Radiatior fan was not turning on.
I'm glad it helped.. yup, those fuses are hard to see if they are blown
Thanks for this video. I don’t have that problem on my Sonic, but I just happened to be scrolling through random videos on CZcams and this one caught my attention. So I’ve gone ahead and saved it in case one day I experience this issue. I have a Sonic Repair video folder I keep videos like this in. Thank you 😉👍🏼🔧
Thank u so much. Blown fuse. Only $5. Saved me a bunch of time and money 😃
Thanks for the vid man helped me alot with fixing my fan I realized it wasn't working because the heat warning came on but was just a blown fan fuse you saved me alot of money most likely appericate it!!!
you're welcome. I'm glad it helped you.
You saved me so much time!!! Thank you thank you!!!!! One 40 amp fuse problem solved!!
Glad the video could help you.
Chevy don't add a temp, oil pressure and battery gauge in sonic. Making those car into money making scams. My sonic only had 108k and don't warn me it was heating up and low coolant. It ran fine but as I checked all my hoses they bubbled up causing leaks, then my fan was always on almost melting the connection to fan. I checked my thermostat, all the seal where cooked but no warning for low coolant or codes' I mean nothing, now it showing signs of bad head gasket' little milky in coolant' I was like wtf chevy car from hell. Should of got a toyota, nissan or ford' I focked up
chem dog you are so right my girlfriends car had the same thing now its a bad headgasket the echaust started smoking so bad it filled the whole block with smoke it was a nightmare now i have to deal with taking the bullshit car apart to replace one headgasket cause we were curious on why we had to keep adding water to it after all of that it never turned on the temp light on or the low coolant light it sucks this car just sucks in general
Yeah tell me about it, I'm 4000$ in debt from engine failure when it NEVER warned me of a thing and I still owe 7000$ on the car. Fuck Chevy for this, FUCK Chevy for this
That's why you have to check your coolant and not be lazy
@Al Dunn You are right about questioning why the fuse blew. Just replacing that fuse and assuming the fused failed because of "old age" is a BIG mistake. Fuses fail because of excessive current flow, not just fatigue. The next step, once the fans are working, is to throw a clamp meter on the fan wires to determine if the current flow is within normal limits.
Mine too. My Sonic is a little over 60,000. Im having the overheat issue right now. My mechanic was SURE he fixed the problem. Were gonna watch this video in hopes we can find the issue. Im not doing American cars after this. Honda or Toyota for now on!!!
Thanks!, That darn 40A fuse was blown and as you stated it did not look blown. I had to remove the fuse and plastic cover to actually see that it was blown. In my case the fan was bad too. To test fan, unplug and connect the 1st spade to Ground, and the 2nd spade to +12V, then move the +12V to the 3rd spade. Both times the fan should come on. Looking at the fan wire socket there are 1, 2, 3 spades with 1 being on the brown wire side and 3 on the red wire side.
dreupen glad it helped! And thanks for the information.. I'm sure it will help too!
Hi. Well, thanks for the video! I had he exact same problem with my car. Wish i could have found this video sooner. God bless
Jesus ochoa-vega great to hear it helped you! thanks for the note
Great video! My son's 2016 temp gauge just came on... Hopefully it's just the 40 amp. Thanks for the info
There’s a low speed and high speed relay for the radiator fan, and fuses for each, hence the 30A (low) and 40A (high) fuses. The radiator fan plug has three terminals, where the middle is the ground and the outside two are-you guessed it-the low and high speed power inputs. The low speed power terminal actually has a resistor in series (to create the low speed). You can check the fan’s low-ground and high-ground circuits with a multimeter to rule it out.
Yep! My fuse was blown! I also double checked the coil of the relay, and compared it to the other identical relays. Noticed that the resistance of the coil was about 20% higher on the coil of the fan relay. That leads me to believe that the coil is going out, causing the fuse to blow. Changed both for about $10!
I'm glad the video helped.. sonics are interesting for sure
almost 4.5 years later I have been screwing around on my wifes sonic, and totally forgot start cheap work your way up. (she usually takes hers to the shop) and since my daily is way easier to work on (motorcycle) its one of two things for me. I keep forgetting to look for fuses and relays. Thank you!
Glad it helped you.
Thank you sir, you are soo correct. You saved me a ton of money. God Bless. Stay safe from Arkansas
Glad to hear it
Thanks for this bud!! My '12 sonic is my daily driver to keep my miles low on my pickup and it just started overheating on very hot days, but cool days it was fine. Long story short the mechanic said $325 to replace the fan shroud but it was just a blown relay!! Fan worked instantly!!👍👍👍👍
I'm glad my video helped and saved you money. Thanks for tge note
Will be looking at same issue on Thursday. Fan doesn't come on. Fixed the coolant leak today, drove around and that overheat symbol cane up then realized fans not coming on. Great video. Thanks
Let us know what you find
Will do 👍
@@russelmccombs so yup it was the same 40 amp fuse. Thank you for the video
Thank you for this video! It was really helpful and I was able to fix it :)
I'm glad the video was helpful.
FYI, thanks for this video, the fuse was exactly my problem
I'm glad it helped you
Thank you sir, nice video. I Chevy Sonic 2012 1.6L. My fan is working good (when turning on AC and other times), but my temp light sensor never appeared before, even when I had major problems of water leak or oil mix in coolant or so. However, check engine light was showing sometimes and some error codes (like coil issue), but never saw the temp sensor light during 7 years. Is that normal? And should it show in the computer test as an error code if it was faulty?
Thank you so much for this video!! Much needed!
I'm glad it helped!
Thanks dude this video was very helpful the sonic i was working on had the blown fuse
Great to hear it helped!
Thanks!! Solved my neighbors problem.
Its crazy how many have the same issues.. glad it helped
You just saved my car and my wallet 💞 thank you, you wonderful soul 💞
I have to say, Ive never been called a wonderful soul. But I like it :) thanks for sharing your experience. I'm glad it helped you.
@@russelmccombs honestly thank you a hundred times bc i had to mechanic places (one was a gm dealership) wasting my money telling me they dont know and replacing parts tht didnt need to be replaced 🤦🏼♀️
Your video is truly saving cars n wallets 🚗💙
Thanks for making the video, you saved us a bunch of money!
You're welcome. I'm glad it helped you.
The issue with sonic's in general have engine cooling system failure. If your fan keep kicking on, it has heat problems. I found trapped air leaking in my ratiator system last week, in the same time destroys all my hoses, ratiator, thermostat, seals, oil cooler without warning' I mean no codes or anything. Also Chevy position the hoses lower then the cylinder head and Same goes for the reservoir and sencor's, why?. Over all chevy did Shity engineering on those cars.
Worked for me Russ! Thanks very Much!
I'm glad it helped
Much needed advice. Thank you so much
I'm glad it helped!
I replaced the thermostat that came with the new sensor on a 2016 1.8 I couldn't get that plug to plug back into the sensor. After many attempts trying the connector both ways, my granddaughter got it to plug in. I took that plug off and I'm sure it's on wrong. The warning light went out , but the fan doesn't come on when the AC is on . I'm going to apply 12 volts directly to the fan as you suggested. But what do you think could that thing being plugged in backwards make the fan not work but still shut the sensor warning light off.oh the sensor has little square part sticking out on one side. The other side also has a little plastic part sticking out but it is beveled not perfectly square on that side. that's the side I think releases when you press the tab. the release tab is currently pointed towards the square one which is facing towards the engine block.
Each fusebox has a white clip that's a fuse puller one side does mini one side does those 40a and 30a j type.
Great explanation thank you for sharing
5 Stars and golden jelly beans for you...sure enough it was the fuse 40 that was shot...$ 5.75 fixed the problem....a bad day for my mechanics bank account..
glad to hear, glad it helped you
We are having the fuse blowing issue with my girlfriends 2013 Sonic 1.8 as I type this. I thought maybe it was a fluke that it blew the 40amp fuse the first time. So far, I have checked the cooling fan, it spins freely, no wobble or roughness in the bearings inside it. I checked the wiring, cleaned connections with CRC electronics cleaner, there are no melted wires, no marks or chaffing on any of the wires coating. There are no fault codes. In the past, this car has already had 2 thermostat changes, new antifreeze both times, Redline Water Wetter put in the second time to try to stop/slow down the corrosion that these things make in their cooling systems that prematurely stick thermostats open or closed, which causes the cheaply made thermostat to kick the, High current flow detected code. But back to the fuse blowing. I have swapped the small dark gray 8430 AC compressor/cooling fan on relay with another. Thanks to your video that shows the proper location for the Cooling fan/ac compressor on relay. But it blew the fuse again. We have let this car sit for two hours running in my garage with the ac system running on the high setting, ac compressor cycles like normal, the cooling fan kicks on and off into high like normal, it blows ice cold air, but take it out on a road and drive it or get stuck in traffic and it blows the fuse again, which causes the ac to stop working and it flashes the overheat light on. I have since ordered the two larger lighter gray relays that control the low speed and high speed sides of the fan. They are the relays in your video with the 120002967 part number. They are the two larger square relays below the 40 and 30amp fan fuses. One is low speed fan relay, the other is the high. Top relay right under the 40amp fan fuse I believe is the high speed fan relay. The 120002967 number is obsolete and is replaced by GM part number 13500118, these relays are a darker color. I have yet to replace them because of our sometimes conflicting schedules, but will comment again if it cures the problem.
But just to add something that I seen and read on RepairPal. 2008 and up Malibu's have the high speed cooling fan fuse issue as well, and GM's so-called "fix" is to put a 10amp larger fuse in and replace the wires running to the cooling fan with larger wires.
Thanks for the great info. No one has been able to answer why the fuse blows in the first place... it does seem a model glitch... and maybe the Malibu solution you found might work here too. It's a crazy car for sure. Let us know
Russ M You're welcome.
I was able to replace the relays a day after I commented on your video.
So far, The Sonic seems to have stopped blowing the 40amp cooling fan fuse.
I'm not 100% sure which relay may have been at fault, so I replaced both just for peace of mind and because the car has just over 100k on it.
But if it helps anyone else who has a Sonic that keeps blowing the 40amp fuse and everything else checks out ok and is working properly.
They may need to replace the low and high side cooling fan relays.
If the relay/relays start to fail and will not hold contact to supply steady continuous power to the cooling fan, the constant kicking on and off may be causing enough of a power surge or if the relay is some how shorting out inside, it will blow the fuse.
From what I gather, the Sonic 1.8 needs both the low and high side relay circuits to engage, cycle, and run/operate the cooling fan speed/speeds as needed by the cars cooling requirements.
So its possible if one of these relays stops working properly, it could cause a excessive amp load on the high side fuse causing it to blow.
If I understood the cooling circuit and wiring diagram correctly, the fan comes on on the low side first and immediately cycles to high right after , so instead of it going from fan off to fan on high, it has a very short two stage/step cycle to engage the fan on to high speed so there is no excessive amp load on the high side fuse. Low side is a 30amp, and the high side is only a 40amp, so its understandable why it transitions from low into high this way. Its easier on the fuse.
I also believe that is why the 1.8 Sonic has the big resistor coil hide in the upper part of the electric cooling fan shroud. Its another attempt to try to ease/lessen the voltage and amp loads on the cooling circuit of these cars.
I have seen that the Sonic with the 1.4 turbo has low, med, and high speed fan relays, and I have not seen many problems reported with fuses blowing on the turbo cars. There may be less of a strain on the cooling fan circuit because they have low, med, and high cooling fan relays and the fan is able to cycle from low, med, and high as needed.
But I don't believe I would want to just pop in a larger amp fuse like the Malibu "fix". Because even if the wire size to the fan is increased, the rest of the circuit has not been upgraded and may cause even bigger problems down the road.
@@russelmccombs Thought I would give you a update. Its been over a month after changing the high and low speed cooling fan relays.
We have had weather in the 90's here on and off and the AC is still working.
Hope my information may be of some help to anyone with a 1.8 Sonic that blows the 40amp fuse from time to time after the car starts getting high miles on it.
@@russelmccombs Car has been ok for 5 months now.
I've been having same issue, so I'm going to try this out thank you.
Does the fan run in 2 speeds? It’s hard to test it out, just switch a new fan in myself, the fan runs for a few seconds and then off when I turn on the AC, and back on after like 30 seconds. It’s going on and off like that….it’s snowing cold here, don’t know how long I should the idle until the engine is hot enough to kick off the fan
I have a 2012 Sonic (1.8) which overheated this past summer. I suspected it was the resistor for the fan which is right at the plug for it. With no actual proof of what it could be I simply cut the resistor off and wired a relay and a switch to the fan 0 $ as I had the relay and switch on hand. It's not the best situation because you have to be aware of when to turn on the switch. I am in Canada, so overheating season doesn't come often.
Thank you so much! My 2014 Sonic overheated while sitting in the drive-through and the next day I got an engine code from auto zone, they told me it was the temperature sensor going bad. I replaced that, and I was sitting in a parking lot idling with AC on and AC started blowing warm air and engine overheated. My engine overheated sitting in a lot and sitting in a drive-through, both times I was just sitting there so I checked the radiator fan and sure enough it wasn't blowing. Saw this video and replaced the 40A fuse and that did the trick. Now I just wonder why it blew to begin with. Thank you for posting!!!
Glad it helped. It seems a pretty standard issue.. there have been hundreds on this video alone. Good luck
ive changed the coolent housing, and then the tank. what is causing the system to crack on a newer car?
Awesome stuff. Thanks for sharing.
Thanks for watching!
thanks man your video help me out & saved me a lot of money so again thanks man .
jason stride glad to hear it helped
You are awesome! I checked everything you did and was anticipating having to replace my mom's thermostat. Then you showed me the fuse and it was obviously blown. I also replaced it with the 30 amp to cover the trip to the parts store. Thank you so much! Just wondering, do you have any thoughts on why that fuse blew? A blown fuse is the result of a faulty circuit and I am suspicious that the fan may be the problem.
there have been over 140 cars with the same issue... (just replying to this video). I think it's an issue with the model.. I doubt its something "broken"... I think it's "how it is"... if anyone finds the reason for the fuse to blow, let us all know :)
Still relevant sir. This helped!
I'm glad it helped
Thanks you VERY much for doing this. 2015 Sonic with 33K miles. It started overheating in traffic with the alarm sounding. It was the 40 amp engine fan fuse. I swapped the interior fan 40 amp fuse to get me to the parts store. Have you continued to have any more problems with this fuse? I did buy a second fuse to keep in the glove box.
This is my son's car, I have asked him how it has been running and he says all good. There seems to be issues with this system in the Sonic (from my searches), keep an extra fuse is a great suggestion... we kept an extra too ;-). And you are welcome, the shops where my son is wanted $150 to even do a code pull and he's in a state that doesn't allow auto parts stores to do it for free, so I hopped this might help others... glad it helped you.
On the way home from work yesterday my 2015 sonic rs was fogging up the outside windshield, no light came on. But when i got home and went near the engine it was blistering hot. Hoping that was just a fluke... but will definitely check the 40 fuse... thanks for this video
I hope my video helped.. please let me know if it was a fuse causing this issue. Good luck
Was there any coolant visible on hoses, engine, etc after the high temp indicator came on? Just checked one of the fuses on my son's and it does look like it's bad. However, I did see coolant around hoses
Not on mine.. use a tester to check the fuses.. by eye you might be able to tell
Thanks for the great video!
I did the thing you said about the j fuse I actually bought 1 40, and 30, then I did the ac turn, the fan unfortunately doesnt cycle on or off with ac on, now I will try try changing just the tstat, and not the housing unit,
Try running 12 Volt's to the fan the way he explains it. Fan should come on instantly, if it doesn't the fan is definitely bad regardless of any other fuses sensors switches whatever.
Thankss, i just got odb2 screen to check the cooling temp, my temp goes to 108 and then the fan kick, there is times that it goes to 111 , is this normalv
40A fuse was my problem. thanks!
pakaroki great to hear! Thanks for the comment
My keeps burning off coolant, i just check it every day and add water. And its buring oil. Seems like after i top off thr fluid its okay for a few days and they i have to redo it.
Excellent video.
Thanks for this video... 😃