Alternator? Ground?
 

I just bought at 1993 318iS. Coming home from work at night, I noticed the battery light coming on, but barely. As I get the engine up to over 3K it disappears for a while and returns. After about 10 minutes of driving, I noticed that all of my dash lights are brighter and the battery light is off.

Earlier in the week, I turned on my high beams and my ABS light started to flash. Also, my radio will turn off and on by itself.

The previous owner replaced the alternator, belts and battery in August 2012. Do I have a bad alternator or a grounding issue? Anybody been down this road?

I believe that you will find a chassis ground beneath the computer connector on the passenger side wheel well. I traced a ground problem on one of my '97s to this connection, and I found that ground to be corroded on both my '97s. There should also an engine-to chassis ground strap around the passenger side engine mount. It takes a lot of splashing so I would remove and clean that as well.

Thanks for getting me started to look in the area. I looked underneath my passenger side for the engine to chasis and saw a ground wire. On my car, the ground wire looked good and it was tight.

I took out my alternator and found that there was a ground wire on it, but it was "naked", meaning it didn't have a rubber coating around it. The ground wire was awfully corroded. I made a new ground wire using 8 guage wire and I believe this has cured my problem. I will know if a week or so if it was a truly a permanent fix.

My 1st BMW and I'm learning!