2002 E320 4matic wagon 110k, Alternator error light just came on. There has been a rhythmic grinding sound & feel coming from the alternator so i'm not surprised.

Needing information:
- 120 or 150 Amp?
- Any special notes to keep in mind when DIY?
- is this a DIY rebuild?
- If yes, where to buy the rebuild kit.
- If no, best place to buy a Bosch reman?
- what's a fair price to pay?
- should i be checking voltage regulator?
- with voltmeter, 15.6volts at battery while car running
- what's the proper voltage range when measured at battery while running in park with no accessories on? with accessories on?

Thank you,
Steve
Campbell, CA

 

15.6 is extreme high! dont run the car at this point my friend! you would burn some electrical components (like: cluster, a/c control) blower regulator, radio, etc) you have a bad voltage regulator! replace it & make sure you get voltage in 13.6 - 14.2 range no more than this.. check for a bad front/rear bearings in the alternator for the grinding sound

Fabio Daniel

 

Thank you Fabio. On this vehicle, is the voltage regulator a separate item from the alternator, or is it internal to it? Any recommendations where to buy a new one in your experience / postings?

Ciao, Stephen

 

The VR is a separate unit and that sounds like the problem to me too. Also agree with Fabio that 15.6 is too high, be careful.