ACRB

Found out from the dealer this morning that my S550 need a special module. This module controls the inner electronics, such as the display clock, the controls to the left side of the COMAND screen and the night vision. Big question…… does anyone know the number of this part? Greatly appreciated?

Mike5215

Didn't the dealer quote a replacement price and give you the part #? (If not, call them back and get it)

vsix

^^^ Communication is the key

Mike5215

Right? Usually they can't wait to tell you how much it is.

ACRB

Well, they told me that it's $1100.00 installed. I didn't ask the part number. A local indy mechanic said that it sounds like BS..... he had never heard of a module that controls these particular electrics, and that it is probably a fuse issue. If I ask the dealer for the part number, it could get ugly. then they would know that I have no intention of letting them fix the car.

Mike5215

Christ, are they the Mafia? Just call the service dept back and ask for the part number. Then immediately enter Witness Protection.

ACRB

You’re absolutely right! I shouldn’t be intimidated at all!

Mike5215

You can hunt the part down salvage on EBay and still have them install it. No guarantee of course on the part but there are no moving parts in a module.

ACRB

With your expertise with these cars, have you ever heard of a module that run the controls to the left of the display screen, and the clock synchronization? Personally, (and admittedly this is my first MB) it sounds like it could be more of a fuse issue.

Mike5215

Not specifically, but the car has microprocessor control units all over the place. The steering column alone has three that I know of. The good news is all those processors will let you know their status via an MB diagnostic terminal. I'm guessing the dealer's service department hooked your car up and the module reported a fault.

ACRB

Terrific, thank you for the insight. Final question..... is the MB Diagnostic terminal exclusive to dealers only? Or would you find quality indy shops with them?

Mike5215

Indy would have to have one to service anything 2000 and up. We need Konigster on here. He knows all this stuff.

Nuru

ACRB, did get the fault/code number and title yet? Or you can ask for a screen print of the issue from the dealer, if your car is still there

ACRB

Yes, they Service Manager wrote down 221 905 5200. This seems to be the code for the center climate control, and I can't see how it could be related to the issues that the car is having. I am tempted at this stage to take the car to another dealer that has a very low mile 2010, and trade in the 2007 that I just bought. Even though my existing 2007 has low miles, and all the work has been done at authorized dealers in the past, I think I'm off to a rocky start. If I picked up the 2010 it would have a full warranty, not just the 3 month powertrain warranty that came with the 07. Also, I would take a lose on the trade in.... Besides the exterior cosmetic differences, (Lights, etc.) are there any other significant differences between the years? (07 vs.10) Thanks again for the input.

triniexr

I'm having some trouble too. My radio, cd, card reader, etc is saying "Device not found". I'm also not getting audio through GPS or Bluetooth. I took it to an indy and he said "Tuner Amp". He cost me $250. I didn't believe him because he had trouble explaining the issue to me so I took it to Benz. They said its the amp in the trunk, cost me $139. I bought the amp for the trunk and had another indy install it, cost me $450. After all that I am still having the same issue. I now have to take it back to benz for them to deal with it. FML, this is going on for over a month now. I bought the amp off EBay because the dealer wants $2500 for a new one. I got the one off EBay for $1200. I'm hoping they can finally solve the issue. After I may just unload my car and go with something else.

ACRB

The car is currently at the mechanics getting fixed. The piece that I did buy was the black plastic control panel to the left of the display screen. Hopefully that’ll fix the multitude of electrical problems.
Somehow, I don’t think it’ll fix the Nite Vision, and clock issue…… but maybe I’ll be in for a pleasant surprise.

Mike5215

All the toys are on a fiber optic ring. Each device, even if it's not in use, is responsible for passing the signal on to the next device, forming a closed loop.

If one device fails, it will cause a cascade of failures in the other devices because the ring is no longer closed. If it's a device you don't use anyway, like Sirius radio for example, you can just bypass it entirely and close the loop.

I would start with a visit to a shop with an MB diagnostic terminal. The car will report which device has failed, then you can decide how best to proceed. It may be the amp but any device in the loop that fails...or blows a fuse...will cause the "device unavailable" error.

DaveW68

I've heard many times that replacing the clock fixes a multitude of problems when the COMAND and other systems go down.

ACRB

Just returned from the mechanic, and the black plastic display panel did not make any difference. I think your approach sounds like a good one. I'll suggest that in the morning when I call them up. Thank you......greatly appreciated!

ACRB

I've, also heard that. Be great if its that simple.

Nuru

ACRB, the number you provided is a part number which brings up the following descriptions:
A221 905 5200 SWITCH BLOCK
A2219055200 - Switch assy lower, w/o aux heating

Wherever you take the car next, ask the service technician to provide you with a screen shot of what the DAS/XENTRY terminal presented as the error codes.

If you are considering trading in your car, I would recommend a 2012 or newer to get more years of warranty, even though, that time line is getting shorter all the time. A 2010, if it has a service date of sometime in 2011 would still have the baseline MB warranty, if the miles were within spec, and 1 year of CPO-based warranty, if you purchased a CPO'ed car with low miles.

Wherever you have your car now or take the car next, ask the service advisor and/or technician to provide you with a screen shot of what the DAS/XENTRY terminal presented as the error codes and the recommended repair procedures - as the DAS/IXENTRY workstation will present that information to the technician. Once you have that, post a pic here and maybe some of the forum members who are technicians may chime in.

ACRB

For anyone still interested in this thread…. I took the car to another dealer who did a complete diagnostic on it. The general consensus is that it’s a faulty headlight switch- (221 545 1404) and that changing it out will solve all my electrical problems. Only issue is that it’s on back order from Germany. Also, the Service Manager says that the center is changed out and the 2 flipper switches stay put. Looking on line…..it looks as though it’s all one unit to me. I’m tempted to buy one online and try putting it in myself. Is this a foolhardy approach? (I’d save close to a thousand bucks)

Mike5215

There's one on EBay for $95, looks good and they say it's been tested. I'd definitely get it and at least try to install it myself (or let the shop do it. They won't warranty the part but whatever. It's not a common failure item. I never even touch mine.) It looks like it snaps in but check YouTube for a DIY.

Nuru

I find it surprising that a faulty headlight switch would impact a number of device's communications on the CAN bus?

konigstiger

Light switch is read in by the upper control panel control unit and forwarded over the interior CAN to the front SAM control unit.