Help would be much appreciated with replacing the bulb in the third brake light (in the center base of the tailgate glass). I can't see how to get the cover off. Surely I don't have to go inside the tailgate to remove the whole unit just to change the bulb?

 

I have never changed this bulb in a wagon but I know Mercedes likes to hide things like screw heads, etc. There should be a plastic cover that comes off somehow so you can access the bulb. (I have an E320 Sedan.)

 

Right -- I can see the plastic cover that looks as if it should come off, but I can't find any way of persuading it to do so. I hoped there would be some of those tricksy little MB concealed screws, but no luck so far with finding them. On each side of the plastic cover there is a small diagonal patch with what looks like a roughened finish on it. I thought they might be places to squeeze, and so release the cover from some latching device. But squeezing doesn't result in much movement of the sides of the cover, nor any sign of its releasing.

 

My experience with those little separate patches is they do come off. Try using a very thin and small screwdriver to pry them off. I'm sure you'll find screws behind them.

Russ P