W210 - E300 - What happened!!?? - PeachParts Mercedes-Benz Forum

slowmoe · #1 03-24-2004, 08:15 PM

This morning I pressed the switch to put up the rear blind. It rose very slowly and then stopped in the middle of the window. Unsatisfied with that, I dropped it back down and tried again. This time nothing. Oh well, I thought, it was fun while it lasted - must be the motor or in need of lube.

I then turned on my windshield wipers. They too went very very slowly. I quickly turned them off thinking that my alternator must be about ready to quit.

I then saw the SRS light flask on and off. Afterwords, both the rear blind and wipers worked normally.

What the heck happened!!!???

J.HIDALGO · #2 03-24-2004, 09:38 PM

Voltage regulator/brushes or alternator going bad.

slowmoe · #3 03-25-2004, 07:25 AM

The battery is the origional from 1996. I know it is old, but I had it checked just 2 months ago at PepBoys and they said everything looked great.

The car had been running for about 5 minutes before any of this happened. Could it still be the battery?

Anyway to check if the alternator is operating to specs?

TIA

-Dan

sokoloff · #4 03-25-2004, 11:41 AM

I'd say the first thing to go should be that eight year old battery regardless of what Pep Boys said.

Len

cil254 · #5 03-25-2004, 01:32 PM

Quote:

Originally posted by sokoloff
I'd say the first thing to go should be that eight year old battery regardless of what Pep Boys said.

Len

Agreed, although readings can show the battery to be in good shape (holding charge etc...) I would get a new one.
I had this happen to me, the battery was the original one (8 years).

Rick Miley · #6 03-25-2004, 02:47 PM

Go ahead and do the battery and have the alternator checked as well. Ask narwhal about his cluster getting fried from a bad alternator.

BTW, make sure you get a battery with a vent tube and connect it up properly. You don't want a battery venting explosive gas under the back seat right next to all those electronics.

blackmercedes · #7 03-25-2004, 05:12 PM

How did the Pep Boys check the battery? Did they do both a static voltage and loaded voltage test? Typically, 300amps or so is a good load for an MB battery. If it's pulling 9V or less, whoops, your battery is going south.

Remember that diesels are a bit tougher on their batteries than spark-ignition cars, as the high compression means a higher cranking load.

Even if it's not the battery right now, that battery is living on borrowed time and replacing it would not be wasted money. However, you should check the charging system. Any warning lamps? ABS light on?

slowmoe · #8 03-25-2004, 08:00 PM

blackmercedes,

As usual - thanks for the thoughts...

PB did both a static and load test. They said it was like new. I will replaced ASAP since it is about time anyway.

I still do not understand how it could be the battery since the car had been running for plenty of time before any of this happened. I am missing some fundamental knowledge here. Can someone please explain?

Should I trust PepBoys evaluation of the alternator?