[hcker2000]

Hey all I was wondering if any one would have any clue as to what would cause the break error light to come on in a 78 camaro?

I can think of a ton of stuff that might but I dont know what kind of error sensors a 78 camaro would have. So I'm hoping some one can narow it down a bit for me so I can get it fixed.

[yesgo]

The light is connected to two different circuits.
One is the parking brake switch, the other is a pressure differential switch.

The pressure differential switch is located in the combination valve... the block where all the brake lines come together. If the switch pin is grounded to the block body, the light will come on. It will do this due to a fluid leak or bypass. The problem must be found and repaired. The valve may reset automatically, or it may need persuation according to factory manual.

The parking brake switch just completes the circuit when that brake is on.

If there is a short in either circuit the light could come on.

[hcker2000]

Ok thanks for the info that will sure help out. I have a sneeky idea it may be the parking break switch. At least thats the one im gona check first.

Now if its the other issue how hard do you think it will be to fix it?

[poncho62]

If the emergency brake is not totally released, the light will stay on........pull up on the emerg brake pedal.

[yesgo]

Depends on the cause. Check the fluid level in the master.
Normally on the GMs, if it's working right, the swich will offset when you put on the brakes, and the light will come on, but when you let off the brake, it goes out. Sometimes it gets stuck on, or you might have one that doesn't reset itself.
An offset differential switch could be caused by anything from a bypassing master to a leaking slave cylinder, or anything in between leaking. Or it can offset and stick during routine brake work.

Unplug the parking brake switch. If it's in that circuit, the light should go out. If it doesn't, unplug the wire at the combination valve. If the light stays on with both unplugged, you might have a short.

edit: d'oh, and first do what Poncho62 said

[hcker2000]

Thanks for the tips. I will get on it. So far the car still stops ok but i dont wana get to the point where it dosnt.