C5 Corvette - Battery Parasitic Drain Test

I want to test this C5 2000 Corvette Hardtop to find out if it has a parasitic drain on the battery, or not.
C5 Corvettes are demanding enough on the battery. All cars have some amount of parasitic drain on the battery. This one should have approximately 0.025 Amp (25 milliAmps).
Car manufacturers generally design the electrical system so that the car should still start after being parked for 30 days.
Rule of Thumb: Take the Reserve Capacity of the battery (RC) divided by 4 = max allowed milliAmps for parasitic drain. 100 divided by 4 = 25. The acceptable parasitic drain would be 25 milliAmps.
Another example: A vehicle with a 30 mA drain and a fully-charged 70 RC battery will only last 23 days.
Here is a link to a chart for converting milliVolts reading from each fuse to amps. Be sure to select the proper chart for the type of fuse that you are measuring with your multimeter.
www.powerprobe...
Watch your amp meter on your battery for 15-30 minutes to ensure you catch any intermittent parasitic drain that may only spike every 10 minutes and only last for a minute or two. More expensive meters have a MAX setting to record the highest measurement to catch any intermittent spikes, but the spike should last a few minutes so you can manually watch your cheap meter to observe it.
Note: I used a 12-volt low-amp OBD2 connector under the dash while making the transition of disconnecting the battery negative post and connecting my Fluke multimeter in-line. Then I removed the OBD2 connector during the parasitic drain test. This prevented a temporary power loss to onboard computer systems.

[@superrainbowfire1]

Thank you so much! Going to try this tomorrow as I’m pretty sure I have a parasitic battery drain. Now I need to find the culprit.

[@JohnsGarage]

Best of luck!

[@Emilthehun]

Awesome! Just what I was looking for. My c5 keeps draining the battery and can't seem to figure out what it is. Add insult to injury, replaced the battery and now the car won't start 😂

[@JohnsGarage]

I am glad you found this video helpful. Good luck in finding the source of your power drain.

[@otonielaburtobermejo4774]

That made me laugh cuz it happened to me lol

[@Emilthehun]

@@otonielaburtobermejo4774 😂. For me it turned out to be the ignition switch. After I changed it , the car is perfect.

[@FrancoisTCS]

@@Emilthehunmay I ask how you came to the conclusion?

[@Emilthehun]

@@FrancoisTCS by measuring current draw, so started pulling fuses.

[@cellenzobertaggia5839]

John: Won't the sleep timer restart when you reconnect the battery when you put the meter inline to measure the current?

[@TeamLazers]

Thanks! Helped me out alot!

[@JohnsGarage]

I am glad you found this video helpful.

[@TeamLazers]

@@JohnsGarage I'm in the process of tracking down the draw on my C5.

[@delaguiar]

Hi. So I disconnected the negative battery post and the negative cable. Now, when i touch one electrode of my multimeter to the negative battery post and one electrode of my multimeter to the negative cable the reading it shows me is O.04 A. Is this ok? Or is it a parastic draw? Because whenever i check my battery voltage in the mornings it shows me 11.94 V.

[@ajcates9136]

You saved me thank you so so much

[@JohnsGarage]

You're welcom.

[@JohnsGarage]

You're welcome.

[@castlegarage6969]

Passenger seat switch unplug it and draw will go away that's one or the body controle module.. been there done that your welcome people