Battery/Alternator Visit workshop!
So for the past couple months i have been getting a warning sign for Battery/alternator, i took it to the stealership and they told me everything looked fine. The alternator passed the test and battery was brand new (replaced it 4-5 months ago). As winter came along the sign started coming much more frequently probably about 2-3 times a week in the morning at a cold start this was when I used to live in San Jose where the weather wouldnt really get that cold, however i recently moved to San Francisco and as many of you must know it gets cold as SH** out here and yesterday while stuck in traffic the sign for batter/alternator came back! This never happened while i'd be driving and then the car started hesitating in traffic. It would almost feel like it was gonna turn off and i'd be stuck in downtown traffic at 6:00PM
: but luckily i was able to drive back home. As soon as i got home i started searching for threads with similar problems where people said it might be the voltage regulator. I wanted to know if any of you guys have had an experience like this and if so what did you do!?i am kind of freaking out since i have to go back to San Jose tomorrow (45 mile commute) and i dont want to be stuck on the side of the freeway.
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Mike T.
dont go to the dealership.... find an indy or someone to change the alternator
dont spend more than 400
it might die on u when driving since if the alternator stops charging the battery its gunna die...u have very low voltage when driving




The brushes are part of an assembly that includes the
brushes and voltage regulator.
Check with Seacoupe he found an inexpensive souce for the
voltage reg module.
The module is just like 2 screws on the top of the alternator.
Costs is less than $100.
OR you can take it to an auto electrics shop and have it rebuilt.

If you are going to replace the alternator, replace it with the same type that came with the car, while it does not make sense it seems that those that replaced their Valeo with a Bosch ended up with problems and vice versa as it throws errors
Last edited by Boom vang; Dec 9, 2012 at 01:31 AM.




It's different than mine on 2002. But I can tell you I can pull mine in about .5 hr.
You might need to pull it to get access.
It just depends on whether you have money to burn or not.
500 isn't a bad price from a mechanic.
But you could DIY for much less. What part of SJ are you in?
I did a lookup on EPC it shows the VR as PN A0031543406.
Thats for a bosch. They don't show anything for Valeo.
I pulled a VIN from Ebay from a 2004 C230 to get the pn.
Parts.com has it for $66 + shipping etc. 69 from getmercedesparts.com
which is a dealer in Maryland. Or you could buy a rebuilt alternator for
around 125 online. Try calling Paeco (Pacific Auto Electric) in Sunnyvale,
and see if they have any sitting on the shelf. They rebuild on the spot for about 150.
Last edited by C230 Sport Coup; Dec 9, 2012 at 03:41 PM.



