I am having an electrical problem with my ’83 SD. The battery drains to dead when the car sits over night. This is a new problem that has just started in the last two weeks. The battery was replaced last July after four years of faithful service; it just got old and tired. About a month ago I got the car painted. The paint shop left one of the doors ajar for two weeks and drained the battery to dead, real dead. We jumped it and it charged back up fine.

I changed out my AC about two weeks ago. I put in a new compressor, drier and converted to R134. The AC works great. Because of the timing I thought that I must have shorted a sensor or something but I went over it and all is well. Also, I went on a trip last week and left the car at long-term airport parking and disconnected the negative terminal. When I got back four days later I re-connected and the car fired right up. So, I’m thinking it’s not the battery.

OK, here’s my trouble shooting so far. I disconnected the negative terminal on the battery and hooked up an amp meter. The reading, with everything off, was 55 mA. I then took each fuse out, one at a time to see if I could locate a short. Nothing happened till I got to the fuse for the clock/radio and I dropped to 25 mA. Then I went back and removed ALL the fuses. I still got a reading of 25 mA! I could not figure out how I could have a 25 mA drain with all fuses out until I noticed that the positive terminal had a secondary wire on it to an alarm system that was there when I bought the car but didn’t work. I disconnected the wire and dropped to 1 mA.

I thought “Eureka!” right? Yep, well it still is loosing juice overnight. And I am at a total dead end here.