Rear SAM Unit Coding ~ Problem
As some members know, I performed a 2012+(Facelift) LED tail light retrofit a while back. I purchased the necessary components to make it happen, such as the W204 Facelift Rear SAM(Service Acquisition Module) unit and obviously the OEM LED tail lights. Everything worked as intended tail light wise with by no means, fog lamp errors or half brake illumination. Apparently however, I discovered that majority of the time if you are using a Facelift Rear SAM on a pre-facelift W204, you will loose complete functionality of the rear sunshade. In my case, since the unit I bought originated from a w204 without the P1 package, I also lost my heated seats. So all together everything worked flawlessly but the heated seats and rear sunshade.
Today, I decided to see if I could fix this little problem. With the help of STAR Diagnostic, I chose to see if I could find a loophole around this loss of functionality. I went ahead and factory reset everything on the SAM unit and re-code it with the options linked to my VIN number. Well what do you know, the heated seats and rear sunshade work again flawlessly, but little did I know another situation occurred.
I thought I conquered my situation; everything worked flawlessly. No error codes were being threw on and I checked the tail lights for any loss of functionality and everything was perfect....Until night time.....I started up my car, and received a "Check Rear Fog Lamp" error code. I headed back to the tail of my car, to see what was wrong and both the fog lights were on.
So I apparently now have an error code, and both fog lights are enabled on my car only at night time. This really frustrates me as I am a bit nervous I cannot fix this problem. It does not look broken which is good, since both of them are lit up, but I would rather be courteous to the driver behind me and not blind them.
However, I haven't lost any hope yet. Since I rambled enough to clearly express my situation, I can finally ask my question. My question is that since I have a W204 facelift rear SAM unit, is it any possible to code off these fog lamps? The reason I ask instead of just performing myself, is due to the fact that I do not know where to go. Hopefully someone out there knows what they're doing and could help and guide me into the correct area of the diagnostic.
I believe I am in the right area, I just need a confirmation from someone. Below is a picture of where I am talking about. If I am in the correct area, could you please tell me the proper settings for the fog lamps as it is hard to translate it since it is in the German language.

Last edited by w204_Generic; May 10, 2014 at 10:38 PM.
I would translate it, but there are a bunch of drop down options when you hit the arrow next to the wording in the German Language.
That would be awesome if you could show him this link!
As for star diag the snapshot seems to be the correct sttings. Since you have access to developer's mode you should have tried to code your OEM SAM first.
As for star diag the snapshot seems to be the correct sttings. Since you have access to developer's mode you should have tried to code your OEM SAM first.
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I managed to get everything to work as intended. The tail lights have no fog lamp errors anymore and the best of all is that my heated seats and rear sunshade work the way they are supposed to.
Also, I have managed to code pre-facelift rear SAMs as well. With the use of a 2013 W204 and my 2011 W204, we can successfully use these two cars, to work together in the re-programming process.
The first step is to remove the SAM on a pre-facelift car and install it inside the 2013 W204, so we can correctly program the tail lights to function accordingly. Then, we take it out of the facelift W204 and insert it back into my car to program the heated seats and rear sunshade. Then there you have it, a successfully coded pre-facelift Service Acquisition Module!
But I have happy to say we can code pre-facelift rear SAMs to function properly with LED Tail Lights.
Last edited by w204_Generic; May 18, 2014 at 02:04 PM.
But I have happy to say we can code pre-facelift rear SAMs to function properly with LED Tail Lights.
Pm sent, w204...
The reason a pre-facelift rear SAM programming works on a facelift W204, is the fact that we reset the SAM completely and VIN code it to the car, so everything works properly. We then place the rear SAM back inside my pre-facelift w204, so we can properly code back on the factory essentials in the pre-facelift car, such as the rear sunshade and the heated seats if necessary.(P1 Package)
The reason a pre-facelift rear SAM programming works on a facelift W204, is the fact that we reset the SAM completely and VIN code it to the car, so everything works properly. We then place the rear SAM back inside my pre-facelift w204, so we can properly code back on the factory essentials in the pre-facelift car, such as the rear sunshade and the heated seats if necessary.(P1 Package)
Here is a guy that did in on his 2009 in march this year.
https://mbworld.org/forums/5973053-post15.html
Here's the original thread and where I got the pdf from as well.
https://mbworld.org/forums/c-class-w...ml#post5973053
Last edited by aznmode; May 21, 2014 at 09:39 PM.
Also, I do not know if this is correct as I never confirmed it and read it on here; the coding with the .pdf can only work on very early versions of the 2009 model. (That guy must have got lucky, as he had an earlier model 2009 W204. So maybe this statement is true.)
Even if you do try this method, make sure your independant shop coder has DAS and not Xentry. The .pdf you gave me is for DAS in developer mode and will not work with Xentry.
Also, I do not know if this is correct as I never confirmed it and read it on here; the coding with the .pdf can only work on very early versions of the 2009 model. (That guy must have got lucky,a s he had an earlier model 2009 W204.)
Even if you do try this method, make sure your independant shop coder has DAS and not Xentry. The .pdf you gave me is DAS and will not work with Xentry.
So when are you gonna do the FL steering mod so you can figure out how to program the steering button lights
I would rather save my money for aesthetic modifications and/or internal upgrades. 
At the moment I am waiting for a vendor on here to visit their manufacturer over the summer, so they can asseble a pre-facelift rear diffuser with big fins for me that fit my dual exhaust.
I would rather save my money for aesthetic modifications and/or internal upgrades. 
At the moment I am waiting for a vendor on here to visit their manufacturer over the summer, so they can asseble a pre-facelift rear diffuser with big fins for me that fit my dual exhaust.

I've seen all round FL one go for $519 USD with airbag. Had I known you were interested I would've pointed it out to ya.
I'm thinking about going big fin as well to replace my diffuser but I have quad setup currently with oem c63 diffuser. I think the big fins would look awesome on a dual. Kind of double thinking if I made the right choice going quads. Harder to convert back.
I've seen all round FL one go for $519 USD with airbag. Had I known you were interested I would've pointed it out to ya.
I'm thinking about going big fin as well to replace my diffuser but I have quad setup currently with oem c63 diffuser. I think the big fins would look awesome on a dual. Kind of double thinking if I made the right choice going quads. Harder to convert back.
After all...nobody could even see the steering wheel unless they were in my car, since I have 5% tint all around and 35% on entire windshield
I am doing the same job for my W212. I am trying to code my new facelift same unit. The problem I have, I can't find a new facelift car so that I can code my SAM unit there. Any clue to do it without using a new car ?
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