Battery light on - need new alternator?
 

The battery light on my 240D has been on for the last several days, though it's been quite dim. I confirmed that the light hadn't been lying to me when I found out my battery was totally drained and I couldn't start the car. I installed a new battery from one of my other cars and the car runs fine but the light is still on so I stopped driving it. Does it sound like all I need is to replace the brushes in my alternator or do I need a new alternator? If so which one (55 or 65 amp)? If not, how do I replace the brushes?

Chances are you can do just the brushes, or the voltage regulator assembly that includes the brushes. I see them on EBay a lot.

Most people would not know about the brush issue, and would replace the whole alternator. But most likely the windings in the alternator are OK. Just the brushes no longer making good contact.

Ken300D

Had same problem...new brushes fixed it
 

In fact, my mechanic's guy actually had the new brushes snapped in before the boss had time to finish writing up the ticket...cheap fix, too.

Why I love these cars.

Hi dieseladdict.

www.**************.com has them and
come with instructions how to install.

Louis

Thanks guys for the replies. So I take it there's no need to remove the alternator to replace the brushes. Does anyone have a picture of the brushes? Louis, can you post a link to the brushes on that website? I can't seem to find them.

Just click "alerts and tips"

Scroll down abit you'll see "voltage regulator failure"
click it then click the picture.

Louis

Well I just came from underneath the car after removing what I thought was the voltage regulator, but I didn't find what I expected. It's not like the one on this picture, instead there's black plastic on the inside with two wires, green and red, coming out of it and connecting to the rest of the alternator. I also noticed on the back of the alternator there's a little black box hanging from a wire. This box apparently has a ground connection to the back of the alternator but the connection is broken. Does anyone know what this box is? I tried to connect it the way it's supposed to be, but my battery light is still on.

So it looks like my alternator has an internal voltage regulator that can't be easily replaced. Am I looking at replacing the whole alternator?

The black box is the condensor (capacitor) (noise suppressor). If the wire is broken off, they're cheap enough to replace if it's too close to solder it. Get back in there and get that regulator...for the Gipper. ;)

jbaj, if the regulator looks like the one on this picture, I don't see how it will fit in. Like I said I seem to have a different kind of alternator. It's a Motorola but the regulators on sale appear to be Bosch. Maybe that's the problem.