O3' qx4 headlamp issue

[tomcost]

Passenger side "main" bulb out. The one behind the 3 inch twist off cover. Swapped bulbs, fuses, relays, ballast. Everything works in the driver's side headlight, but no combination works in the passenger side. In low beam setting this main bulb does not illuminate, on high beam the bulb below this bulb does work. Any ideas? Thanks in advance.

[fueler]

If you have checked fuses, relay, ballast, (and bulb??), then could be a bad stalk switch on the column? Is the ballast getting proper signals to turn on?

[tomcost]

Thanks. Way over my technical ability. I did systematically switch over fuses, relays, bulbs, ballast. Everything works when plugged into the wiring to the driver side headlamp. No combination works plug into the passenger side headlamp. I in a hardware store with a repair shop, so I have a pretty good troubleshooting resume, but I have no background with this automotive wiring. Just really baffled that everything I have checked works in the driver's side wiring, but not in the passenger side. I know this is high voltage, do how would I make further tests?
Thanks!

[restart52]

If you have Canadian vehicle with daytime running lights, first place I would check is cold solder joints in the daytime running light module on the fender beside the battery.