I just put on the 99 sport headlight assembly on my 94. I had to cut a hole for the 2nd bulb since i only used 1 bulb on my 94. 1 bulb is a dummy bulb and the other works. the only one that works is the high beam bulb. I just used it for the first time for 4 hours straight and they went out on me. My signals still work but now no headlight bulbs work period. and they are $20 a bulb. Any ideas. I have even tried old bulbs and still nothing. Did i burn up my harness or something?

 

Did you check the fuses? Make sure you check everything that deals with your lighting system. Wires, fuses, voltage etc.

 

Also make sure you have good grounds. A bad ground will cause this problem.