Ok... need a little more info here... but if the high beams work manually, but not with the auto dimmer, my first guess would be that you have a faulty relay somewhere in the system. If the highbeams don't work at all (manually or otherwise) then I would guess the highbeams could be burned out, or you could have a faulty dimmer switch / relay. Good luck!
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Your headlights may not dim because you don't have dimmer lights. Dimmer lights can blow and leave you with just the high beams.
If your high beams still work it is the dimmer switch.
Normally caused by faulty dimmer switch.
You may need to replace your dimmer switch.
I would suspect the dimmer switch or "combination switch".
the dimmer switch is going out if you are experencing that.
To find the cause of the low beams not working, start with the bulb to make sure both are ok. Check the dimmer switch, and the wiring from the switch to the headlights.
If your high beams aren't working on your 1996 Firebird, the issue could be related to the headlight switch, the dimmer switch, or a blown fuse. First, check the fuse for the headlights in the fuse box; if it's blown, replace it. If the fuse is fine, the dimmer switch, which is part of the turn signal lever, may be faulty and could require replacement. Additionally, ensure that the bulbs themselves are functioning correctly, as burned-out bulbs could also cause high beams not to work.
It is on the side of the steering wheel and is used for turning your headlights on and off it is also used to control your high beams and low beans
dimmer switch dimmer switch
try checking ur high-bea fuses and relays
== == more than likely your dimmer switch is bad,hope that will help