[wambus]

I have a 98 Passat. 277k.
Recently I replaced the factory headlights and corner lights with a set of aftermarket OEM style housings. they are not great, but are super clear compared to the clouded original ones (I kept the originals and may try to clean them off the car). The issue is that a few nights ago, I started noticing that the lights were not looking right. I determined that the low beams are on they are fine. But when I turn on the fog lights, the driver side low beam shuts off. At first it would come back on after a couple of seconds, but now it does not. When I turn on the high beams, the low and high beams do not work on the driver side. Help?

A sidebar to this is that I was pulled over one night for no tail lights. Once I got home I found out how to pull the main switch. I did this and unhooked it from the harness. I plugged it back in and for fun checked the tail lights. They were working.....

I apologize if there is a thread on this already, but I cannot find one so far and need to drive the car in the dark tomorrow and am concerned about the lights....

 

[cuppie]

At a glance, the problem with the driver's headlight yells at me "faulty ground splice in the headlight!!!" Quick check (to determine if fault is in the light, or elsewhere in the car):
Because you still have the OE lights, plug that in, and see if it functions normally.

"Lights broken, but work after monkeying with the switch": That one tells me "switch is dying, and needs replaced." Yes, people will tell you "troubleshoot!!!!" But, generally, when playing with a mechanical switch causes normal operation to resume, the switch is the cause of the malfunction. And, after 20 years, and nearly 300,000 miles, it's not out of the question for the switch (any high-load mechanical switch, for that matter) to just start dying.

 

[wambus]

I will try plugging in the old light. If it is the fixture, what am I looking for to repair?

Is the main light switch a switch I can take apart and clean? I did that with the window switches in my 1987 Supra with great success....

I forgot to mention, the day-time running lights have not worked for several years. Is that also switch related?

 

[Marooned]

cuppie's suggesting remaking the grounding splice that you modified at each light, since physically moving the connection makes things work or fail. I'd echo his thoughts on the combination switch/headlight high low beam switch/turn signal stalk, for which you'll have to remove the steering wheel and disconnect the air bag. Bad grounds on VW's can cause huge headaches and are worth attending to carefully. Check the grounding screw if you can access it and clean it up as needed, then use no-ox and put it back together Can't hurt to check fuses and relays, either. Relay 173 is for daytime running lights on the B5 Passat, I believe. This thread might help. I've never heard of this switch being serviceable, but it may be.

 

[wambus]

let me note that my headlight switch is on the dash, not the stalk on the column. Also, the replacement headlights were OEM so I did not alter the wiring in any way to install them.

Does this info change anything stated above?
Where is the grounding screw?