battery drain 1983 300 SD TurboDiesel

Hi,

Glad to have found your forum, apologies if this question has already been addressed before. Last May I inherited the an old family Mercedes. It's a beautiful car with only about 120,000 miles on it, in terrific shape.

About a week after I got it the battery died and I replaced it. For the next several months I had no problems and it fired up every time. I was driving it one or twice a week. Yesterday, after not having driven the car for about a month or so, the new battery was dead, completely drained and unable to hold a charge. I switched it out with another new battery under the warranty, fired it up and then disconnected the battery so it doesn't keep draining out on me.

I'm not much of a mechanic...I'm guessing there is a short or an open circuit somewhere that slowly drains the battery when the car sits for an extended period. Any help or ideas anyone might have would be very appreciated. Thanks much.

try this at night, or in a dark garage, with the doors closed check out the interior lights and make sure none are on, the vanity light on the passenger side is a common culpret of this problem also sometimes it can be that the light in the trunk is staying on also check the glove box and ashtray lights. :smile:

Thanks very much. Went through some of the old posts yesterday and noticed someone else had a very similar problem on the same make and model.

Hoping it's something very simple like a light switch staying on. Hadn't noticed any lights on before in our dark garage at night, but that vanity light is concealed so will check that this evening. If I can convince my wife to eventually let me out, will also climb in the trunk and see if the light stays on when it's closed. Appreciate the help.

Power antenna, power antenna, power antenna. Just a guess here, but checking that first always was a good time saver for me. Disconnect the antenna and see if the drain is still there. Do you have a drain tester?