Cruise control stopped working in our '97 GC SE 3.3. The CEL is on showing P0104 or whatever the EGR code is. Cruise has worked with this CEL before. The CRUISE light illuminated when I press ON but it won't set. Any tips on diagnosing?
Or the brake pedal switch is failing. The switch is actually up to 3 switches in one. One for the rear brake lights which is normally open and closes when you step on the brake, one for the PCM brake sense which is normally open and one for the cruise which is normally closed.
When you step on the brake pedal, it cuts power to (opens) the cruise control circuit so that the cruise is disabled. If this normally 'on' switch is open, the cruise won't engage but the cruise light can stay on.
Sometimes it is adjustable.