123 chassis taillight problem
 

I am having an intermittent problem with the left taillight on my 1982 280e. It will occasionally go out, but if you bang hard enough on the hood, it will go back on. The other bulbs on that side all work fine. I have tried cleaning contacts, changing bulb, etc. However, the problem persists. I had the same problem with my 1981 300d that I never solved. Any help would be much appreciated. My son was given a warning by the local police last night because the taillight was not working.

I don't know how different the W124 housings are from the W123, but those metal rails that run along each of the bulb receptacles can get unseated from the plastic track they are attached to...just enough to lose the ground connection and cause one or more bulbs not to light up.

An easy test is to remove the housing and press down along the entire perimeter of the metal rail with your thumb and see if the bulb comes back on...