One Headlight Functioning - Bulb is Good

Oct 14, 2005 2 Replies

I'm driving a 1989 300E. My right headlight is not functioning on low beam. However it works at the high beam setting.



I've switched the bulbs from left to right, and it clearly is not a problem with the bulb. Any well known problems with the switches, wiring or connectors known to anyone here? Any trouble shooting suggestions?



Thanks in advance!


Have you checked the fuses? I haven't got the diagram at my fingertips, but Mercedes wouldn't be dumb enough to fuse left and right beams together. You can't always detect a burnt fuse by eye, so put another in to be sure. Otherwise, you've got a wire off, or a bent prong in the connector.

I tried swapping the fuse and it didn't help.

Twice in the last several days the right headlight turned on... so the problem is intermittent. It came on when I started the car with the high beam switch turned on, turned on the headlights, then switched to low beams. Suddenly both of the low beam headlights were on!!!

Is there a relay that controls the lights that may be the culprit? Any other tips to diagnose the source of the problem?

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required