Battery drain
Cruising
Joined: Apr 2022
Posts: 11
Likes: 11
From: Texas
Relays were mentioned and I’d like to circle back on that and suggest looking into those if everything else otherwise checks out.
On late C3s, the courtesy light timer can go bad, causing enough of a draw over time to drain the battery. I’ve had that problem before. Are your courtesy lights currently working correctly?
Also consider that it could be the anti-theft relay. I had that issue in my ‘78 Pace Car. For me it was the last place I looked (of course!) but ultimately that was it.
The other thing I would do, just to see, is pull the battery out of the car and hook up the tender to it to see if it takes and holds a charge. That way at least you can get a good idea of if your tender is malfunctioning and if the battery is toast or salvageable. It is probably the case that the tender is okay, and your parasitic draw just outpaced what the tender could do to save it while in storage.
On late C3s, the courtesy light timer can go bad, causing enough of a draw over time to drain the battery. I’ve had that problem before. Are your courtesy lights currently working correctly?
Also consider that it could be the anti-theft relay. I had that issue in my ‘78 Pace Car. For me it was the last place I looked (of course!) but ultimately that was it.
The other thing I would do, just to see, is pull the battery out of the car and hook up the tender to it to see if it takes and holds a charge. That way at least you can get a good idea of if your tender is malfunctioning and if the battery is toast or salvageable. It is probably the case that the tender is okay, and your parasitic draw just outpaced what the tender could do to save it while in storage.
Last edited by RPOZ78; May 12, 2025 at 12:02 AM. Reason: Typo
