PeachParts Mercedes-Benz Forum - View Single Post

bhatt · #6 03-23-2008, 05:20 PM

I think you may have hit the nail on the head....

I replaced a 2 year old Interstate battery with a new one, since it wouldn't properly hold a charge. The shop did do a full test on the battery and said it passed with flying colors. They only replaced it because they said that one bad cell could be the problem, and that wouldn't show up on the test.

So perhaps the alternator has been intermittent.

I did a voltage check at the battery (with the car at idle) about 2 months ago, just before I replaced the battery. It was 13.0 or 13.1 volts (can't remember).

Is it possible the alternator was charging at 13.0 volts then and 14.0 volts now? If so, I have an intermittent charging problem.

Or could the "supposedly bad" battery have caused the charging voltage to be low at 13.0 volts somehow (can't see how this could be the case, since I was testing voltage at the battery terminals...)

I'm going to pull the alternator and swap the voltage reg/brushes next weekend. Other than that and the wiring harness, is there anything else that could cause the symptoms I mentioned? The only other thing I can think of is replacing the entire alternator but let me know if there is anything else I can check before I get into that.