Replacement Fob Buttons?
Well I had the same issue. The red color button pad fell off in my pocket. I later found it in pieces. The dealer quoted around $200.00 , And needed personal ID , car registration and 3 days to have it replaced. There was a small Thread here that someone went to a E-Bay site & typed in Mercedes Benz Key FOB. sure enough there was replacement covers & blank key blade ! for $9 - $12 , But this is the fun begins. For $12.00 it gets to my Door. It looks pretty nice too.
So off to the work bench. The OEM FOB needs to be opened up to transfer the internal Parts IE; IC chip & Circuit board and Key Blade. Well the OEM FOB is sonicly welded together. You Got to cut it apart carefully !! you will stab yourself & bleed profusely. You got to be handy with small tools & Have good eye sight too. The IC chip transfered over , but lays loose in the upper right corner, held in-place by a white nylon hold down piece. Which doesn't fit as nice on this new FOB as it did in the OEM FOB. I had to hand fit it. I ended up putting a drop of gell type super glue on the bottom make sure the print is facing up! . Now placement of the Circuit board seems to fall in-place pretty good. the 3 black buttons work fine , the Red panic button, works if you apply a lot of pressure to right of the middle, I have to shim the rear of the Circuit board up about the thickness of a Tie wrap !! Man I'm thinking this is a pain in the A$$ , and I already destroyed the OEM FOB case. and can not turn back now!!. So now I test the Buttons and they all work properly .
Next Issue , if you can believe it. The OEM key blade is small in width than the blank replacement. So It will not Transfer over to the new Case. This is a Lazor cut key & not many hardware stores have a Lazor cutter. Now I got to find a good Lock-Smith. $40.00 later the blank key is Properly cut. If they screw up , your screwed , because they carry only the thiner base replacement blade. Now I have $53.00 dollars into this new well working China made replacement key and 1 & 1/2 days of my spare time plus gas . Was it worth It!! for me yes . I like challenges. But this job may not be for everyone and & save over $100.00 too