Replacing alternator brushes / regulator on car


Active member
Oct 10, 2005
Ottawa, ON
2002 Jetta GLS Black
This saved me hours of work and hundreds of dollars! Thank you!

My 2002 Jetta, with 348000 km finally stopped charging. This thread helped me pull the old regulator off, and buy a replacement (knock-off) from my local garage for $75CAD. I could have bought one a lot cheaper online from Sofia, Bulgaria, but the delivery time was about three weeks.

The dealership quoted $512 for a new alternator, or $155 for a new regulator. At a local auto parts store, a remanufactured alternator was $284, and a regulator was $105.

I'm happy now.

**A note that Step 6 (remove 15mm nut) should come after Step 4.**
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Veteran Member
Jan 7, 2012
Greater New Orleans area
2001 Jetta GLS, 2003 Jetta GLS Wagon
Valeo vs Bosch

So my 2003 TDI Jetta wagon has a Valeo alternator which just started making the battery light illuminate on my instrument cluster and 11.5 volts show on my scangauge instead of more like 13.9 volts.

The disassembly process to access the regulator on my 2003 ALH TDI Jetta wagon's Valeo alternator is similar to the Bosch but not exactly the same.

I'll double-check the Valeo nut sizes and update this post when I go to reassemble things.

On my Valeo alternator
I carefully removed the plastic cap from the big main B+ wire's nut with a flathead screwdriver,
I removed that wire's retainer nut from the B+ stud, 13mm I believe,
I removed that wire's retainer clamp nut from an alternator housing stud at the opposite corner from the B+ wire's stud,
I lifted the locking tab and unplugged the 2-wire connector off the regulator,
I removed the two 7mm cover retainer nuts with a deep socket and the cover easily slid off.

At that point there are just 3 small bolts holding the regulator to the alternator housing and a plastic brush assembly cover/cap attached to the regulator.

The Valeo regulator is completely different from the Bosch versions, I don't see any part numbers on the regulator itself, and a google search isn't helping so at the moment I don't know what a good replacement regulator part number for my 120A Valeo alternator is and the ones I am finding are all far more expensive than the Bosch ones.

My primary reason for adding this post to this thread is to let others know that there is more than one brand of alternator available for these vehicles and different types of regulators that are not all interchangagle depending on the brand so you need to look at what alternator you have before buying any parts.


Veteran Member
Nov 7, 2002
DC (really Fairfax county, but it is easier to say
2003 Jetta TDI Wagon, Reflex Silver
This thread just made my life so much easier. Isonic’s update with pictures and the differences he noted were especially helpful.
Last Friday, my car started getting an alternator workshop code that was going on and off. I have the full MFD so it might just be the battery light on other clusters. When I got home I open the hood and poked around. My battery voltage was low but I could hear my alternator engaging and then turning off. It wasn’t getting the battery charged enough so I figured it was the regulator.
Following the advice here I ordered a no name one off eBay for $25 from some place in Chicago and was lucky to have them ship that day so even with a holiday weekend I received it on Tuesday. Took an hour on Wednesday morning to install. Everything is working great. As a bonus, my right HID was having issues igniting and with the new regulator that issue is resolved! Thanks everyone!