greg12m3

So a few days ago I was out around 3am cruising on the highway. I wasn't really speeding I was going a nice and steady 60ish but then I gave it some gas, and get up to 90-100 and get a warning saying "Battery/Alternator, Visit Workshop" I stopped on the side of the highway and turned the car off and let it sit for a minute. Started and drove off and for about 10 minutes the warning was gone but then once I got on the gas again it popped back up.

So the next day I brought the car to EuroMotorcars in Bethesda and had them perform some tests on the alternator, voltage regulator and drive the car. They concluded nothing was wrong and charged me 90$'s to tell me that. Anyways, hearing this I left and took the car out and drove it pretty hard. Again the warning came up. I have been driving with the secret menu open to value 24 which is the volts of the car right? The car when turned on and sitting in Park is 13.5 maybe a drop to 13.3 but no lower then 13.1. When the car is warming up it's around 12.4-12.9. When I'm driving civilized it will vary between 13-13.7 and drop every few minutes below 13 for maybe 10 seconds. But when flooring it the volts drop to 12.1-12.7 and sometimes maybe even a little lower and right after flooring I get the warning.

Any Thoughts?

The car just went through a bunch of maintenance work at euro and they are assuring me it is in excellent condition and a good example of the breed. It's at 112k now. Also the battery isn't a mercedes battery, I think it is a red top something... but i'll check in bit and post that.

Also, They wanted 1270 for the alternator job, and thats just ridiculous, surprisingley for the work they have done for me their prices have been competitive (service B, gaskest for trans/engine connect, gasket for rear diff, tie rods, ball joints... ). But would anyone recommend pelican parts for their rebuilt alternators?

Thank you!!!!

Eurosport

don't know about the alternator, but i can vouch for Pelican Parts, they good and fast shipping too

how old is the battery btw?

greg12m3

Cool, I think i'm going to be ordering my alternator soon from them. The battery is only half a year old, maybe not even yet but has about 25,000 mi on it. I think this maybe related to the cold as it's warmer today and the warning hasn't come on much today only twice right after warming up. Mainly when it's colder out does it come on more.

Fabio D

You can check your alternator wiring harness.. I have the same exactly problem but in a W124 (500E) is not very common this problem in the W210, but check not cost you nothing! the wires aislant broken in the 124 end in a short circuit with the other wires & the voltage regulator unactive the alternator some times.. Check them

Fabio Daniel

greg12m3

thanks, would the wiring harness be at the alternator itself? Mercedes checked over the alternator and voltage regulator so if the harness is there i would hope they checked it.

Fabio D

The alternator have 2 wires in the back of them, this 2 wires go to the car system. you only need to view the back of your alternator & check if the aislant in the 2 wires are ok or are broken. if they are broken your workshop need to replace them

MASTERBENZ

DOUBT THAT'S YOUR PROBLEM. VISIT MY SHOP WWW.MARSAUTOGROUP.COM

-MAR-

greg12m3

Eh... thanks but no thanks, I went to your shop before, I wasn't very satisfied...

Anyone else have any ideas? I think I'm going to go ahead and order the alternator from pelican parts and put it in.

Fabio D

You check your wiring harness? it's all ok?
Befor purchase the complete alternator you can buy only the voltage regulator. is the most common faulty piece in the mercedes alt's! is very simply to replace too.. only remove the 3 little screws in the rear of your alternator to remove the black cap! before you can replace your voltage regulator removing "2" 8mm screws. and... run your car!

greg12m3

I did check, everything seemed fine. I brought the car to Curry's in Great Falls, Va. They did a road test and then were going to test both the alternator and voltage regulator but after the road test the mechanic had no doubt that the alternator was about to go. The volts kept dropping to below 12 above 50, under full throttle. I was pleased with Curry's.

SO, I have ordered my rebuilt alternator from Pelican parts and will have Curry's put it in. Fabio, thanks for you input, also i'll be sending you the pictures of the exhaust as i remember you were interested in the dual set up. When it goes on the lift next week I'll be able to get some good pictures.

Thanks!

Fabio D

Yeeees i'm not forgot that, Many thanks bud i apreciate it.. if you want my e-mail address let me know!

Thanks in advance

Fabio D

greg12m3

Brought my car to Curry's yesterday as my alternator arrived 2 days early! They were very quick, my friend was suppose to pick me up but being because of his laziness he arrived 20 minutes before they finished, only took 2 hours or so. They also replaced the belt and did an oil change. The problem seems to be fixed, no alternator/battery error, the volts never drop now below 13.5. I was very happy with curry's service, for those that are interested I went to the one in reston/great falls.