Why would the battery keep going dead in a 1986 Cadillac Coupe DeVille if the alternator is good?

Answer 1

Had the same problem on my '93 DeVille. After removing all lights in trunk, under hood, etc, replacing the battery several times, I found that someone had dumped loose change into the rear passenger side ash tray and a penny fell into the empty cigarette lighter socket. When the lighter was put into it's place, it would drain the battery and yes, it did cause a wiring harness replacement. This solved my problem, maybe yours will be cheaper.Answer If your caddy has a load leveler try disconnecting the fuse, worked for mebad battery or your wire harnest is bad Answerwhy my battery keep going dead in 89 Ford crown vic

9 out of 10 times it is going to be a defective voltage regulator in the alternator. If you hav gone over the vehicle and have not found a draw, your going to want to check that voltage regulator.