Bad Alternator or Voltage Regulator?
 

Went out for some runs with a few buddies the other night.
Nice casual Monday night....

Ran my friend's FBO E60 M5. He just recently installed his headers.
Car has amazing top end. I need a pulley upgrade to have a chance.

Then I ran a 2012 C63 P31 with 2nd cat delete... walked all over him. Good 3 cars I'd pull everytime.

Then out of nowhere I get these warning lights on the dash.....

https://cimg9.ibsrv.net/gimg/www.mbw...fcadbd76a4.jpg

https://cimg0.ibsrv.net/gimg/www.mbw...f021704ee0.jpg

https://cimg1.ibsrv.net/gimg/www.mbw...e89b63bc6a.jpg


Nursed the car to my friend's house that was close by. Parked it overnight. Next day went to the shop and borrowed a booster pack to be able to drive it over. Back to my buddy's house to get her going....

https://cimg9.ibsrv.net/gimg/www.mbw...1e19f61f0f.jpg

I was a little nervous about the brakes giving up on me... being electric and all. As I made the turn to the street where the shop is located, lost power steering and all brake feel.... used the E-brake to be able to turn into the garage.... man was I lucky.... timing is everything.

And here she sits.....
https://cimg1.ibsrv.net/gimg/www.mbw...1fe3f44770.jpg




Been doing a bit of reading... and some say voltage regulator solves their issue. I noticed a plastic burning smell though... so I'm thinking my alternator is just shot. Any insight?

Thanks guys.

https://cimg7.ibsrv.net/gimg/www.mbw...e623f38b3d.jpg

This happened to me about a year ago. I pulled the alternator and took it to a repair shop. They reported that the internals were good, but the rectifier had shorted out. This is what caused the burning smell. They suggested replacing the bearings as long as the alternator was out of the car. Total cost for rectifier and bearings (part and labor) was $130.

"Brake Malfunction"
"Stop Vehicle"

That's quite a conundrum...

Plastic burning smell is the alternator. was such a pain to replace. Take the fan shroud out and disconnect all the radiator lines on the front passenger side.

lol...

Exactly what I said when that warning came up lol

I have a new OEM Bosch voltage regulator I can sell you that I bought as a back up a few months ago. Let me know if you want it.

I can see the 2 smaller intercooler lines that are in the way. Can you clarify if you mean actual radiator hoses or the smaller coolant hoses that go in and out of the intercooler on that same side. Thanks

I took out the radiator lines (the big hoses). Also the double pulley came out. Made it much easier to get the alternator out without puncturing a radiator line. I heard you could squeeze it through the lines but I wasn't able to do so.

here is my situation with the voltage in the car

its a 2006 cls 55 amg


at idle does not charge, shows battery voltage
when i rev it up around 1500, voltage goes up to 14, 14.1 volts

while driving tends to stay around 14v, but as soon as rpms drop, seems to stop charging

any ideas?

has your alternator been replaced or is it the original?
front battery and rear battery original or been replaced?
If all 3 above have been replaced, then would look into battery relay thats under the windshield or the battery control module in the trunk, black box by the bumper

i am not sure but not changed for atleast 2 years for how long i have this car

batteries both show good voltage 12.5 volts when car is off and hold the charge for days

BCM in trunk should be working fine, i tested battery with negative terminal and it shows same voltage when tested against car chassis as negative (thus it should skip the BCM i guess), tested while car is running ofcourse

i can test the battery relay, any photo or info how to get to it? and how to test it

http://www.benzworld.org/forums/atta...ator-relay.jpg

is this it? how do i test if this works or not ?

thats it under the passenger side windshield.

I was recently in the same situation then I replaced the voltage regulator, the battery and after all this I found it was the alternator so just go for the alternator

Why not just buy whole new car while at it

Good point next time alrernator needs changing I'll buy a new whip lol

Since the light came on while you were driving, it's likely the alternator. Change the VR first, you can get to it underneath the car. You just need to remove the plastic and there are like 6 screws/nuts that hold it on. The parts only like $50-60 so it's worth a shot before taking out the alt.

try replacing voltage regulator. If it doesnt work then the alternator for sure.

you DON'T need to test that relays if your main battery is good.
the K57 relais kicks in only in that case (besides for charging the Aux battery).

both bolts (#2 in the pic) are Positive, and you have a lot of chances to make a short . so, just stay away from it. Warned .

i had a similar warning light, ended up being an alternator.

https://mbworld.org/forums/w211-amg/...ml#post6502327

best of luck

I dnt think it's your alternator or battery giving you the problems...it might be your cranksharft pulley is slipping...( in begining stage) pls inspect the crank pulley..

My guess would be the voltage regulator or the serpentine belt...both would give you that red battery warning...i had both happen to me also 😕

p
 

I want to thank TalonP for post # 76, excellent descriptions and pictures.

My car: Mercedes 2013 E350

After going through steps described by TalonP on post #76, my steering wheel column still would NOT move up or down. I gave up and put everthing back together, resigned of spending $1500 to $1800 at the dealership.

However, I keep on searching for other posts and there was one where they talking about door being open vs closed ignition being on vs off. To satisfy my curiosity, I went back to my car, sat on driver seat, closed the door, removed the on/off button of the ignition so I could turn ignition switch with the key, turned ignition one step before engine would start, push lever down while hitting steering wheel on top, followed by pushing lever up while hitting steering wheel at the bottom towards the ceiling, and then ... the column started to move!

It now moves up and down. However, since I do not know why it stop working, other than something got stuck somewhere, and I do not want to pay the dealership $1500 to $1800 to fix it; I positioned the steering wheel the way I like it, and then I disabled the "Easy on/off" feature so the steering wheel will not move up/down in/out when I get in or out of the car.

TalonP - Thank you so much for your pictures and detailed description.

Cheers,

Flying C

Basically in a nutshell, if you are seeking just best bang for the buck in a serious upgrade without a lot of hassles then you could use just these front S55 calipers along with an R500 13.8" front rotor and it will bolt on fine and need nothing custom and nothing else. you may need a 5mm washer at the caliper mounts but I don't remember for sure and will check to confirm this. that is really all you'd need to do to upgradeHello turbocad, I just wanted to confirm as I have an early 06 R500 with the solid rotors on rear and 13" front brake rotors and stopping acts like front drum brakes! I am very interested in going with S55 from calipers and 13.8" rotors on the front of these will bolt on with a 5mm washer at the caliper mounts. Thank you for all the R&D you have done with these R class brakes! I do only have 17" R350 wheels on my R500 at the moment (bought the car like that) so will S55 calipers clear the 17" wheels?