So I've been googling this problem for maybe a week now and I can tell you I'm absolutely stumped. I have a 99 Blazer with 107000 miles on it that I just bought maybe 3 years ago. I just started it up the other day and I noticed the headlamps weren't working. I jumped the battery to see if that'd do anything, I checked all the bulbs and they are okay. Fuses are all good. They did work for a short period of time today when I put the tilt steering wheel in the up position, and it'd only come on in drive and the high beams would not come on, but after about 15 minutes they turned back off. The parking lights, brake lights, blinkers and backup lights all work. Also, when I attempt to put the high beams on the light will not come on the dash. Is my problem electical? Is it hard to fix? How much would it cost at a mechanic? Thank you for anyone who helps!

 

Sounds like the multi-function switch to me. Check the switch and the wiring.

 

When the lights came on for the short period of time I could pull back on it and the brights light would come on but it wouldn't click in place. So that could be it. Is that hard to fix or is it pretty simple?

EDIT - I was just thinking though... the headlamps wont come on period. So wouldnt it be the headlight switch thing? The parking lights and everything still works its just the headlamps.

 

This is the part that makes me suspect the MFS, especially if the tilt wheel has been used a lot over time causing the wires to fray, but the headlight switch could be the culprit. I despise electrical issues! To replace the MFS you will probably have to remove the steering wheel, being cautious of the airbag. I recommend getting a Chilton or Haynes manual.

 

Bump. Now the headlights work, kind of. During the day the headlights will turn on and at night they will turn off and will not come on at all.... The headlight switch to the left of the steering wheel does work but will not turn the lights on at night. How does this make sense?!

 

Here's the schematic for the headlights (see attached):