Highbeam issues

lately on a 99 grand prix we been having problems with the high beams not turning on. dash lights all go out and fog lights stay on. high beam light on dash comes on.

Sounds like it could be a faulty multi-function switch. Check to see if your brake lights work, with headlights on, off, and with highbeams on.

I agree with Tim, it's most likely either the M/F switch, or the headlamp switch. There's an outside chance it could be the ignition harness/switch, but less likely. Follow Tim's advice and post the results.

brake lights are operating correctly

Sounds like it could be a faulty multi-function switch. Check to see if your brake lights work, with headlights on, off, and with highbeams on.

brake lights work is there anyother way to test to be sure of the problem?

if the brake lights/running lights work, I'd say it's the multi-function switch, the switch that changes from high to low beams is part of it and not replaceable by itself.