Hi,

My A4 (1996 2.8 nonQuattro) has had two peculiar incidents where the battery has run dead without any usual cause. Both came after I had not driven my car for several days, which is a normal driving habit for me. The first time 2 months ago I was walking out to my car and noticed I could hear the radio inside. At some point it had switched on by itself during the 5 days that I hadn't driven it. The radio button was in the "on" position that typically turns off when you remove the keys and it had been off when I previously left the car. As soon as I tried to start the car it did not have enough power to run the radio or interior lights anymore, and the trunk latch could be heard clicking. I chalked it up to extreme cold weather at the time.

The second time was this morning. Again I hadn't driven it in about 3 days. I went to start it and the battery was almost completely down. No driving or interior lights had been left on, the radio button was in the "off" position as I have been leaving it since the first incident. There is no obvious reason as to the drain of the battery. When I turned the key a few funny things happened like the seatback moving down on its own and the trunk lock clicking repeatedly which I assume probably happened from the low battery condition. Weather was normal this time around: 40-60F.

Does anyone have any ideas what the cause of this might be? An electrical short somewhere turning things on or draining it? In between these two incidents everything has been running relatively well and the battery voltage has seemed to be normal. Also, for about a year my cruise control has ceased functioning and the climate-control display comes and goes if anyone thinks that may be related or has any information about correcting them.

Thanks,
Brian

 

did you ever check you alternator to see if it is good. If the alternator isn't doing the job then the car will die so easily, and sometimes random things wont work right because of it.

 

The alternator seems to be fine. Once I jumped it, it is running fine, battery is recharged, and I'm getting normal voltage on the gauge. The problem seems to be with the battery running down while I am away from it either from some accessories randomly turning on or from something else that is drawing on it. I plan to get the battery tested tomorrow to rule that out as the problem. Any other ideas what might be going on?