I need help with this strange electrical problem in my 98 E320. My back up light does not comes on when I shift in reverse. The bulbs and fuses are good. I get current on the driver side but the bulb doese not come on(strange). I do not get current at the passenger side at all. looking at the wiring diagram it is simple and when you shift in reverse current should be sent to bulbs directly. First I tought it was back up switch but getting current on the driver side should eliminate that, however, it does not explain not getting current in the passenger side. Any body knows what could be the problem? I appreciate your help.

 

Bad ground or corrision in the socket.
ohlord

 

Thank you for response. This problem is strange. there is no crrosion any where. all the contacts are clean. I checked the voltage at several places. I get 13.8 v at the plug where it connects to light assembly, at the contact plates of light assembly, and at the socket contacts attache to light assembly without bulb in it. But as soon as I put the bulb into the socket not only the light does not comes on, I do not get a voltage reading at the socket contact either . This is the case on both sides of the car.

If I had grounding problem would I get full reading?