there should be a switch (i think it's called a dimmer switch or something like that) in the underside of the steering column that gets actuated by a rod when you pull the multifunction lever to turn on the high beams. i replaced one years ago. i can't tell you exactly where it is or what it looks like, as i don't remember. i can tell you it's cheap to replace, though.
easiest thing would be to go to a small service garage that does NOT charge to look at problems and see what you need.
1998 BGM Camaro 3.8L A4: [under the knife]
SLP Lid, K&N Air Filter, Magnaflow 3" Cat-Back, Zexel Torsen LSD w/3.08s, 32mm Front Stabilizer Bar, 19mm Rear Stabilizer Bar, Spectacle Solutions SFCs, J&M PolyBall LCAs, 4300k HID Low Beams