pgiii2000

Back right tail light will not turn on. I have ordered andreturned three Bulb Carriers and everyone had the same issue the bottom back rightlight will not turn on.So I switchedthe left bulb holder to the right one and all the lights came on, so I ruledour wiring and SAM issues. Mercedes tried the other returned bulb holders and theyall worked on other models. I am completelylost, and have no idea how to fix this problem. Please Help!

MJ50

moved to X204 forum...
is it for both taillights not working??

pgiii2000

No the only light that is not working is the back right Bottom Bulb. 5 out of the 6 stop lights are working.

Bill F

Are you referring to the rear fog lamp?? It only work's on driver side as explained in the manual

pgiii2000

No the rear passenger side brake light.

Sam.P

So you swapped the passenger rear brake light bulb holder with the driver side one and it solved the problem?

So basically you've pinpointed it to the holder? But what if you put the passenger side holder on the driver side?

pgiii2000

I thought I pinpointed the issue to the Holder, but now we have ordered three different bulb holders from MB and they still don't work. Each holder was tested on both passenger and drivers side connections and the results were the same. The main break light bulb will not turn on...

bop11

Did you try just swapping that bulb from the holder that works to the one that does not?

pgiii2000

Swapped Multiple Bulbs, and multiple bulb holders.. The only thing I could see out of the ordinary is that I used a test LED bulb and it faintly illuminated. To me this seems like a Sam issue, but why would the other driver side( Bulb holder) when switched all lights came on.. I’m lost I’ve spent12+ hours trying to find resolution.

bop11

Did you look at the connector on the end of the cable in the car? The wire for the lower tail light might have been inserted into the point where the fog light is on the left side. Since there is no fog light on the right side that location does not connect to the bulb socket for a right side bulb holder. When you plug the left side holder in, what you actually saw was the fog light turning on for the lower stop light. Examine the vehicle connector very closely for the actual wire location. If there is an empty point that is probably where the connection is suppose to be. You can remove the pin and move it or just jumper the connection point in the bulb holder to it or any other brake light .

Bavariane46

I found this old thread while google searching for this same issue. I have been frustrated with this exact problem for months. My fix was to replace the small sidemarker bulbs (194) type. The sidemarker bulb worked but was sending a signal to the SAM, which caused the SAM to trip the lower bulb into brake only mode. I tried carriers, bulbs, swapping, etc, but the only thing that worked was changing all sidemarkers to new and restarting the car! Do not use LED or the SAM will read the wrong resistance and not light the brake bulb.

NYCGLK

Yep, GLK doesn't like LEDs.