Pontiac Repair: lights dim and car quits running when i press the brake pedal...94 bonneville, pontiac bonneville, speedometer needle

Question
when i press the brakes, only when the headlights are on, the lights dim and the anti-lock brake light comes on. the speedometer needle also pegs out and the car will sometimes quit running. is this an alternator problem or do i have a bad ground somewhere? thanks for your time. the car is a 1995 pontiac bonneville that i recently fixed after having a front end impact with a deer. the airbags went off and i replaced the headlights and hood. the parking lights fuse was blown when i got the car and i replac3ed that.

Answer
Hi Damien:

It sounds to me like a ground issue or a loose connection somewhere. check the battery connections the positive cables are always an issue on this car. the corrosion build up between the 2 cables on the battery. As for the grounds this car has grounds on both sides of the car on the inside fender well. The fact that the speedo freaks out would tend to make me think that there is a ground issue and the lost or bad ground is feeding back through the other components on the car. good luck :}