Battery drain mystery

I have a 1985 Cutlass Ciera that has a battery drain problem. Perhaps someone has had a similar problem and can point me in the right direction.

Car runs fine. Then, one day, it was dead when I tried to start it in the morning. I recharged the battery and drove it to work. At the end of the day it was slowly cranking but failed to start.. It started fine with a jump.

First I had the battery tested (only two years old) but it tested OK. The guy at the part store suggested that it could be the alternator (bad diode). I pulled the positive lead off the battery and checked for a current draw and (something) was pulling 12v with doors closed and everything off (presumably).

I disconnected the alternator. Still 12 volts being drawn.

I pulled all the fuses. Still 12 volts being drawn.

Where should I look next? Is there something, like a relay, that fails or sticks in the closed position? Any help would be appreciated.

Pete

I can't believe the plethora of GM owners with the same electrical nightmare I experienced nearly Two years ago. After going through batteries like crazy, I take it to the GMC dealer, they troubleshoot, trace it to the drivers seat motor has a constant draw on the battery, so they replaced it. Basically, nearly any electrical part that could draw from the battery, did so, and was replaced when discovered. Any problems I ever encountered with this vehicle have been electrical in nature, as my repair order paper trail at the dealership shows. I lost the best job I ever had in part because I never could predict when the battery would be dead as I tried to start it every morning. What it does now is sort of comical. When I step on the brake pedal it turns the rear defog switch on. At various times, intermittently, the auto reverse in the cassette player is audibly activated - even if the power to it is turned off.
My own suspicions make me think the car was miswired on the assembly line. BTW, can anyone help me find the electrical wiring diagram for a 1996 Oldsmobile V6 3.1 Cutlass Ciera SL Wagon? Thanks. Good luck with the mysterious battery actions.
Doe