W211 CAN Bus problems - PeachParts Mercedes-Benz Forum

KrustyKustom · #1 10-08-2019, 07:29 AM

Going to order a genuine Mercedes remanufactured alternator. Tired of playing the merry go round with NAPA refurbished units. Hopefully with them selling me 2 lemons they will give me my money back. They are $650 instead of $200 but well worth my time and peace of mind.[/QUOTE]

Having dabbled with my two W211s on can bus issues the Alternator has to be the backbone of reliability. Another option to going OEM is a Bosch New Unit. I recently ordered one from Pelican and it would be the same as a new MB unit which would likely be be a remanufactured.

I am dealing with a front passenger side SAM unit defective right now and some of these modules are starting to be become rare, the one I need is not in the USA and none in stock in Germany. Supposed to be 4 weeks. The bummer on these newer gen tech cars is if your SAM units/ECM units go there is no subsitute for not getting new modules. You can find used ones, but dealers will not program used parts and unless you have a really old version of the Xentry there is no offline coding available.

jay_bob · #2 10-08-2019, 08:24 PM

Quote:

Originally Posted by KrustyKustom

I am dealing with a front passenger side SAM unit defective right now and some of these modules are starting to be become rare, the one I need is not in the USA and none in stock in Germany. Supposed to be 4 weeks. The bummer on these newer gen tech cars is if your SAM units/ECM units go there is no subsitute for not getting new modules. You can find used ones, but dealers will not program used parts and unless you have a really old version of the Xentry there is no offline coding available.

I was able to get the alternator for around the mid $400s with exchange, or double what NAPA charged. This is a remanufactured unit certified by MB. I need to turn in a core at MB so I am going to just give them the NAPA unit since it will be almost $200 more without the core.

I will be pulling the alt tomorrow evening when I get back from my trip and swapping it Thursday morning at the dealer. Also ordered up new brakes, rear pads and rotors, front pads, so I have another weekend project ahead for this car.

I am too concerned about electronic module failure killing this car. I am glad I was able to save the ZGW module on this car, I guarantee it’s not cheap at the dealer.

KrustyKustom · #3 10-08-2019, 10:44 PM

I have been awaiting the arrival of the front SAM unit for several weeks and it is still showing not available in inventory in the US or Europe. They do not give you a eta when it is awaiting to be made apparently.

So, I have bought a used one. (hope it is good). Taking it to a independant shop with subscription service Xentry to get it coded. I downloaded the code from my SAM onto a thumb drive through my Chinese Xentry, but I cannot upload to the SAM with the C4 version as it looks for a server login.

Working with the CAN-BUS is cumbersome as the vehicle gets older in my opinon but I sure like the W211s!

jay_bob · #4 10-09-2019, 07:49 AM

Quote:

Originally Posted by KrustyKustom

So, I have bought a used one. (hope it is good). Taking it to a independant shop with subscription service Xentry to get it coded. I downloaded the code from my SAM onto a thumb drive through my Chinese Xentry, but I cannot upload to the SAM with the C4 version as it looks for a server login.

Yep that is the problem with the cloned diagnostic units. It’s worse on a 212 and 166, not only can you not upload to the modules, you can’t do the download nor change options (version coding) without logging in. All you can do is scan for faults, run the guided tests, and you can write to the maintenance log (when completing services). Granted that is better than nothing but going forward they really have it locked down.

It’s like the gps maps, on the 211 you can just pop a dvd in there and as long as the data is valid (Meaning a good copy) it will accept it. On the newer models the map comes on an SD card that is hard coded to the VIN. Meaning that you have no choice but the dealer.

On my 211 I bought an EBay copy of the last update that will ever be made (2014) for about $20. MB still selling for $350. I normally don’t advocate piracy (I write code for a living so yeah it’s personal) but come on guys, I am not paying $350 for a 5 year old map that has no support path going forward. I just got tired of it telling me I was off the road every time I drove on a section of roadway near my house that was reconfigured in 2005.

So that same thing will happen to the later models.

I think you are going to see people start offering board level repair of these modules as a service. There are people out there with access to specialized tools and knowledge to be able to troubleshoot these boards.