aposak

First post, hello world! This issue is driving me crazy.

My w211 has halogens (NOT HID). Replaced both headlamps for that like new clarity, and changed over to LED bulbs. Passenger low beam randomly flickers, accompanied by a faint clicking sound like a relay failing from somewhere on the passenger side. Typically happens while I'm driving. I've hung a GoPro off the front, and it appears just the headlight is flickering. Installed the old halogen bulbs, and I can hear the relay clicking and see some dimming on the GoPro video. I think the flickering is more noticeable with the faster response of the LEDs.

I've swapped the bulbs between driver and passenger, and the problem stays with the housing.The housing is new, so no wire degradation to worry about. Wires look OK, and the plugs look reasonably good and have contact grease on them. I can't pinpoint where the relay sound is coming from, or where the relay might be.

I could just leave the halogens in there, but I know sooner or later something will completely fail at the most inopportune time. Can't find any info on halogen headlight issues. Anyone had this issue before?

CaliBenzDriver

before you pull the circuit schematic to replace relay, CLEAN nearby GND posts usually under the side beam. Disconect batteries prior.