1998 tiburon

[jmdc64]

while headlights are on if i turn on the ac/heater the left headlight turns off and signal light wont work

 

[hyundaitech]

Not many ideas, really. Check the underhood fuse box(es) for any burning of contacts. These lamps don't seem to share any grounds with the blower. In fact, I cannot think of any reason why the left headlamp would go out but the right wouldn't. These lamps are in parallel with each other, sharing the same power source and grounds. The issue is with the left headlight and not the parking light, correct?