Measuring Parasitic Draw
Thread Starter
Burning Brakes
Joined: May 2015
Posts: 1,024
Likes: 264
From: Port Charlotte FL
Measuring Parasitic Draw
After letting my 2024 C8 sit for around an hour .. this is the draw I am seeing ... The Milliamps are bouncing all over the place. All the videos I see only show the draw fairly static and not jumping all around ..
Has anyone else did a test on their car? So far my C8 has had the battery replaced twice. The Recall for the 2024/2025 battery drain issue has already been done. Seems each batteries have only lasted about 12 months before needing to be replaced.
Has anyone else did a test on their car? So far my C8 has had the battery replaced twice. The Recall for the 2024/2025 battery drain issue has already been done. Seems each batteries have only lasted about 12 months before needing to be replaced.
Race Director
Joined: Mar 2007
Posts: 11,403
Likes: 8,564
After letting my 2024 C8 sit for around an hour .. this is the draw I am seeing ... The Milliamps are bouncing all over the place. All the videos I see only show the draw fairly static and not jumping all around ..
Has anyone else did a test on their car? So far my C8 has had the battery replaced twice. The Recall for the 2024/2025 battery drain issue has already been done. Seems each batteries have only lasted about 12 months before needing to be replaced.
https://www.youtube.com/shorts/Iz7EodZ13b0
Has anyone else did a test on their car? So far my C8 has had the battery replaced twice. The Recall for the 2024/2025 battery drain issue has already been done. Seems each batteries have only lasted about 12 months before needing to be replaced.
https://www.youtube.com/shorts/Iz7EodZ13b0
I measured mine and reported it here at this thread:
https://www.corvetteforum.com/forums...e-battery.html
Thread Starter
Burning Brakes
Joined: May 2015
Posts: 1,024
Likes: 264
From: Port Charlotte FL
Car was locked and powered off for an hour. Front hood latch was latched but hood open. Meter connected between negative battery cable and negative battery post so entire draw was going through meter. Background sound was a fan in my garage. There is no cellphone service in my garage. I wonder if the car continually tries to connect to onstar or cell service.
I watched your video. I can't see how the meter is connected, but it seems to hover around 70ma. Its not that much "all over the place". But.....it does seem way high. Is something running? There is a background sound. Any doors open or anything?
I measured mine and reported it here at this thread:
https://www.corvetteforum.com/forums...e-battery.html
I measured mine and reported it here at this thread:
https://www.corvetteforum.com/forums...e-battery.html
Race Director
Joined: Mar 2007
Posts: 11,403
Likes: 8,564
Car was locked and powered off for an hour. Front hood latch was latched but hood open. Meter connected between negative battery cable and negative battery post so entire draw was going through meter. Background sound was a fan in my garage. There is no cellphone service in my garage. I wonder if the car continually tries to connect to onstar or cell service.
Also, In order to put the meter physically in series, you unhooked the negative battery terminal, then hooked it back up through the meter. When did you do that? I'm wondering if disconnecting and connecting the battery may temporarily affect draw. And, the battery monitor is there too. From what you described, you put the meter between the post and the battery monitor (see image). That should not directly affect current - it all has to pass through it - But it might (and I am speculating totally now) affect the electrical system in some way when its messed with. It is monitoring the battery even with the car off - thats a fact - its how it calibrates the battery state of charge from the procedure in the Service Manual.
Last edited by Andybump; Apr 12, 2026 at 07:14 PM.
