Since a few days, I have this head lamp issue:

- when I turn on the engine after a couple of hours parking, most of the time, only the right head lamp comes on. On the left head lamp, low/high beam are both not working most of the time. Sometimes the left head lamp comes on normally even after several hours of parking.
- when I then activate the right turn signal, nothing changes regarding the left head lamp
- when I then activate the left turn signal, the left head lamp sometimes comes on! -> seems random. Low/high beam are then both working fine for the rest of the ride
- when I then stop the engine, remove the ignition key, put in the key and start the engine again, the left head lamp still works afterwards
- After a couple of hours parking, issue sometimes starts again. At least that's what I have observed so far.

-> only the left head lamp is affected
-> low/high beam are affected at the same time on the left head lamp
-> all other lamps are working fine
-> behaviour is the same with turning on the head lamp manually (when it's bright outside) or when they turn on automatically (in the dark garage)
-> the behaviour seems random

What could be possible causes?

 

Might need a new multifunction switch, the "stalk" on the steering column, controls all these things.

 

Check fusebox bolts

 

Check the ground location on the left shock tower. Maybe the path to ground is going through the turn signal. Maybe the import mods have something to do with it? Any LEDs?

 

Thank you for all your inputs. Much appreciated. I have updated my first post. The behaviour seems to be more random than I initially observed.

Activating the left turn signal only sometimes help, most of the time not (anymore). I haven't made any changes lately. The issue started out of the blue.

I will check the fuses, fuse box and ground location. No LEDs except for the sidemarkers front and rear. They have been there for years.

 

I haven't had any outages for the last few days. This might be a mysterious loose contact...

I nonetheless checked the fuse box bolts. Everything was tight there. There is normal 12v voltage on the ground location on the left shock tower. As a preemptive measure, I replaced both fuses for the driver side lamp.

Should the issue pop up again, I will have a look at the connector (and wiring) for the driver side lamp. This could be a likely candidate with the symptoms I have seen so far.

 

There shouldn’t be any voltage at a ground location.

 

I meant I checked the voltage between the + connector at the battery and the ground location.

 

That is not the way to check grounds. Check for continuity between a ground and any bit of body.

 

That's the reason for the intermittent headlamp outages... Whatever the cause for this charring is...

What kind of plug do I have to look for as replacement? Maybe someone here can recommend an eBay link?