umm, when I had my new headlight bulbs I had the same problem. But it was the bulb and that specific bulb didn't work on either left or right side headlight, the high beam that is. So I got rid of the bulbs and now the high beams work with the new headlights I've bought.. Check your wiring harness too, might be that. Were you running normal headlight bulbs? Or were they something special?