Kahdmus

My car is losing power, followed by the battery/generator light, followed by PSM warning light, brake warning lights, ABS lights, air bag, etc.

Restarts after battery charge with no warning lights, however battery voltage drops, warning lights start popping up and I lose power until the engine dies.

There is NO low battery warning light on.

Presumed alternator, but as no battery light, wondering if its the voltage regulator?

Is there a way to troubleshoot to deduce battery vs. alternator vs. voltage regulator?

Thanks,

--H

Imo000

Its not the battery but the alternator. Take it off and get it rebuilt. They have standard off the shelf parts, any rebuild shop can do it in a day.

Kahdmus

Reading through some threads here, 6speed and pelican, it seems the same symptoms crop up for a defective voltage regulator - any way to tell if its the alternator OR just the voltage regulator?

Imo000

The regulator is inside the alternator.

Kahdmus

Its attached, and apparently is a cheap, easy DIY. I read a few posts experiencing similar symptoms with a bad regulator and therefore thought it worth asking the question..

Kahdmus

Also..what does a replacement alternator plus labor cost these days? Cheers, --H

Imo000

No idea, I fix my own cars but it me $100 to rebuild the alternator.

fpb111

It is likely the brushes have worn out. The brushes are part of the regulator. The regulator is mounted on the back of the alternator. It is very easy to change the regulator. It's more of a pain to pull the alternator than it is to replace the regulator. If you do a search for alternator or regulator repair there is a thread that has part numbers for the Bosch regulator and alternator. The alternator is the same as one used on a 2004 Mercedes ML350.

see this thread on Renntech.org
http://www.renntech.org/forums/topic...or#entry223820
Search doesn't work for me today, there are similar threads on this site.

wwest

Exact same symptoms, same symptoms sequentually, Costco battery fixed all.

Kahdmus

Test for battery vs.alternator?

kromdom

Cheapest/fastest troubleshooting to do: remove battery, take it to your local auto parts store and have it LOAD-TESTED. If it passes, battery is NOT your problem. If it does not, buy a new battery and problem solved. Best of luck.

CDLVancouver

The exact same symptoms on mine 3 weeks ago. Alternator was toasted.

CDLVancouver

Did you test it all? Or is a fresh battery carrying the load for now?

fpb111

We don't have a Costco near by. Would an Advance Auto battery work as well?

Kahdmus

Picked up a replacement next day. Aftermarket from pepboys, cheap but lifetime warranty. Spent Saturday installing with my son. Had a few challenges getting the old one out, and broke a plastic part connecting the coolant lines, but all is complete, rock solid 14+ volts and car runs great again. Thanks for help chaps!