Battery drain in 2000 Cadillac Catera
Disconnect one battery terminal (+ or -) but not both and place a large lamp like a headlamp (12v) in series with the battery terminal that is disconnected and the terminal that you removed. If the lamp lights, you are getting a phantom power drain. If the lamp lights dim, place a smaller lamp like a signal light; 5 or 10 watts or so. If you have an ammeter, use that instead as long as you can read it from the fuse area as you go through this process.
Go to the fuse panel and in order, remove the fuses one by one. When you remove a fuse, and the lamp stays lit, put the same fuse right back. Keep going through all the fuses until you find one that shuts the test light off. When you find the fuse that causes the problem, the circuit that is fed off that fuse is causing the problem. I had same issue and no circuit raised its head.
It is normal for the car to draw about 20 to 50mA which keeps the clock and other presets alive and allows the body computer to accept signals from the remote door lock. This is very little current for a car battery.
On the 00, 01, there is a multifunction relay located (in my 01 anyway) above the fuse area in behind the dash, it's a grey box about the size of a pack of cigarettes. In it there are 4 or 5 relays, one of them monitors battery voltage when the vehicle is shut off. When battery voltage drops below a predetermined voltage, the relay kills the power saving the battery for effective start.
I repaired my multifunction relay board by re soldering all the traces on the PC board. The relay box is about $80 (dealer) if you don't want to tackle this. After I repaired the MF relay box, my trunk worked everytime, sunroof, radio and fuel door. And best of all, my battery drain problem disappeared. Its been 2 years now.
Jul 18, 2010 |
2000 Cadillac Catera