pinebaron

In the old days I'd buy a set of brushes, a bearing or two, dismantle the alternator and fix it in about an hour. Most alternators can be fixed if they are not completely burnt out. It just happens I can fix almost anything (its actually a curse).

apl175

Update: The dealership still has my car. Attempting more intensive diagnostics. I don't think they've been able to replicate the light coming on, but they understandably want to keep up on their "fixed first time" metrics.
A C-class loaner car has been provided to me for the week thus far. Stay tuned.

vettdvr

We share the same curse!

pinebaron

I just returned from my shed where I finished fixing the charging circuit for my lawn tractor after I purchased a flywheel puller to reveal the stator beneath; God only knows what happened to the puller I used more than 10 years ago. The stator is a little weak (meaning a coil may be shorting); it will do for now but I will have to order a new stator to return the system to its original glory.

vettdvr

I pulled the magnetic ride system out of my corvette and replaced it correcting all the chassy squeeking.

Taylor-Made'90

My battery warning light has come on daily over the last few days. It comes on right after I crank it initially. But after driving 15 minutes to work, it goes away. And the light stays off for the rest of the day. But the next morning the warning comes on again.

Talked to my benz tech friend, he thinks it's the Aux battery...


How much does an Aux battery run?

Can I get one from anywhere else besides the stealer???

What are the part numbers for the main (rear) battery and for the aux (front) battery??

vettdvr

Note prices change. Both batteries are AGM don't be tempted to switch to lead acid.

Main battery Carquest Battery BAT 49AGM-70 12V Europe OE AGM $189.99

Aux Battery MB Part # 2115410001

Autozone GTX 14-BS battery this should be the exact replacement for $69.99
GTX 14-BX FG AGM

Walmart everstart Maxx 14-BS AGM
Interstate CYTX 14-BS (at local firestone)
Delco GTX 14-BS
Napa 740-1866?? Not sure if # is correct
Yacht CTX12-BS ETX-12/12BS
Sears CB12C-A
Yuasa YB12AL-A2

Possible just 14-BS will work.

Battery dimensions

WxDxH 6”x3 ¼”+ x 6”

Note + Terminal is on right side when looking at the back side of the battery.

Taylor-Made'90

Thanks, Vette!!!

Next question: When raising my hood, looking at the engine, tell me where the aux battery is located?

Passenger's side, far corner against the firewall??

Let me know, K?

vettdvr

You are correct but under the cabin filter. You have to remove it to get to it. Be sure to read the owners manual on battery disconnect.

Taylor-Made'90

Thanks, Vette!!!! Your rock....

treddel

Thanks Koenigstiger for the service campaign info, unfortunately mine had it done already.

It was the alternator - was replaced with a Bosch rebuilt one for ~$500.

Thanks to the contributing members of this forum!

treddel

apl175

After 11 hours of diagnostic and repair time, the fault appears to be resolved. The trace was made to rear SAM where they found a short in the wiring caused by "contact with sharp metal of support brackets".
In the end, no components were replaced, just repairs to the wires.

pinebaron

That's a strange one but glad to see it was resolved. It just shows we should never jump to conclusions about causes of battery drain etc.

vettdvr

Wow,, what great work to stick to it to solve an issue. My MB dealer is clearly the best dealer I have ever had in 40 years of car buying. My new corvette had 1 cut wire on the memory seat and the caddy/chevy dealer just kept throwing parts at it without listening to me or getting into the details. I even opened a tech service with the factory and they never solved it. Finally in frustration I pulled the seat out and found the cut wire, repaired it and it has NEVER failed since. Nice you had a dealer that would stay with it.

I would buy him a bottle of his favorite for solving this one.

apl175

I agree completely. The things that makes them stick to it, I'm sure are:
- Preventing a return visit for the same cause (first time fixed right metric)
- Non-defective factory return of parts (I hear dealerships get dinged heavily for this).

The actual service order was of course more detailed than what I paraphrased, and was very methodical. They essentially accessed each interior CANbus test point on the car, and worked their way, with an oscilloscope front to back, until they discovered the short, and then discovered what was disconnected to make the short go away. They did their extensive tests on the rear SAM to make sure it itself was not defective, and then did the physical wire trace from the affected rear SAM circuit.