Right headlight intermittently turns off and on

[SD ///M4]

On my 2006 Z4 M Roadster, the right headlight will intermittently turn off and I get the headlight warning icon on the dash. Sometimes it will go back on again by itself. Sometimes I can bang on the headlight and it will come back on. Sometimes it will come back on again if I turn off the engine and turn it back on again.

All this seems like it points to a faulty connection but I have no idea where to start. I can do a lot of mechanical work on the car but I don't have much experience with electrical stuff, particularly with faulty wiring.

Has anyone else experienced this? Where do I start looking?

[Our03z4]

Any moisture in the lens? My xenon headlights started doing the same thing until it stopped all together. Had a ton of moisture that built up inside and it fried everything.

[SD ///M4]

Originally Posted by Our03z4

Any moisture in the lens? My xenon headlights started doing the same thing until it stopped all together. Had a ton of moisture that built up inside and it fried everything.

As it happens, my wife drove the Roadster to work this morning. I'll check, but I'm doubtful, as this has been an issue for years. I just got the Roadster back on the road after sitting for about 1.5 years.

Edit: I checked, no moisture in the lens. It only rains intermittently 3-4 months a year her in SoCal, so I was pretty sure it wasn't that.

[wdb]

One of the turn signal bulbs in my LF headlight assembly is intermitent. I replaced the bulb and receptacle, no help. I've seen one or two mentions of the wiring insulation in the vicinity of the headlights deteriorating, so that is going to be what I look at next. I hadn't seen any signs of it when changing out the xenon components so I thought I was safe, but maybe not.

[pungo]

The ballast plugs in under the headlight with the pins pointing straight upward. If the seal gets compromised, water can get in causing corrosion for the connection.

The insulation on the wiring does start to crumble and fall apart over time, though the wire itself should still carry the current ok. About a third of the lights I retrofitted with dual AE had crumbling insulation, probably due to environmentally friendly insulation which can't handle the heat from the bulb

I recommend several coats of liquid electrical tape rather then regular electrical tape to repair the insulation.


crumble

[chickdr]

"environmentally friendly insulation" = pain in the A@# for the owner down the road. Nice job BMW...