Headlights work on low but when high beam is selected lights go dead. ocassionally they work momentarily.
Mark

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If your car is mid 90'* I'd suspect the switch itself, if it works a bit when you move/wiggle it. The relay would either be engaged or disengaged with power.

If they come on momentarily, I wouldn't suspect the relay. I'd suspect the switch. At the base of the turn signal lever, a metal rod is attached. It travels down the column to the hi-beam switch. You'll have to remove a couple covers to expose it.

could you go through the steps to replace the switch. my high beams do not work also. im 3 for 3 on cars that ive owned that the high beam switch breaks.

I would second everone else'* opinion on the High Beam selector switch. Very common to go bad on GM products. I've replaced several of these.