Hey folks. Question for yall, I've got an 80 delta coupe and the brakes are fairly worn down in it, definitely need replacement soon-ish, I used the parking brake, which illuminates the "BRAKE" light on the info cluster, but it seems to be that the light will occasionally "stick" on and go away when I push the brakes to stop the car then will come back occasionally, this is the first time I've used the parking brake in a year of owning the car because I never bothered it's a foot brake. Anyone know if this is normal and what conditions need to be met for the "BRAKE" bulb to illuminate?

Thanks folks. Picture for fun.

 

Since the problem started when you used the parking brake after a long time not using it, I'm guessing the parking brake needs adjustment. The pedal may not be coming up all the way when the brake is released, so it's hovering just on the edge of turning the light on.

On the other, I presume you have checked the brake fluid level in the master cylinder.

 

Yessir. Have checked the brake fluid, which seems roughly the same as we left it from last spring.. Upon actuation of the parking brake and a fast release it seems to be fine now.

 

You might clean the parking brake lever with WD-40/Kroil/PB blaster and a toothbrush. After years and years of not being used they tend to stick. At least the one on my 71 98 did.

 

To answer the original question, there are three ways for the BRAKE light to be turned on.

1) the "lamp test" function when the key is turned to the START position. This is a separate terminal and wire from the ignition switch that provides a path to ground for only this purpose.
2) the emergency brake pin switch. This is a pin switch like the ones for the dome light on the door jambs that closes to ground when the e-brake pedal is not fully released.
3) the differential pressure switch. This is the set of contacts in the brake combination valve on the frame rail that closes to ground if there is a pressure differential between the front and rear braking circuits. A pressure differential indicates either a leak in half of the brake system or a problem with the master cylinder.

Note that on cars with the PowerMaster electric brake booster, there is a fourth option. The BRAKE light will illuminate if the PowerMaster system is not building pressure.

 

Two things,

1. My lamp test function does not work. I've tested it just now.

2. We've replaced the calipers and wheel cylinders both were done at the same time, this was before a 2600km trip down to oregon and back from BC canada. the brake fluid level has not changed, and my master cylinder does build pressure when the car is off. (Pumping the pedal a number of times builds the pressure) so I have a feeling it may be the e brake switch like you and others have said. I'm able to make the intermittent light go away for a while by just stomping on the ebrake and releasing it fast with the lever so it's likely that.. this is a mad max/gambler 500 car so it's not really a super big concern, the only concern I have is losing my brakes when I need em most. That's why we serviced them with new fluid and cleared the system out as best as I could before the Oregon trip.

picture to show off my new Christmas lights. Merry Christmas all.

 

You should not have to pump the pedal to build pressure. It should be there immediately. You still have air in the system.

 

When I say pump the pedal I mean extremely softly and maybe 1/4 inch each press while the vehicle is off, just to be clear. Still figure it's got air in it? I've had many cars nearly all of them needed a small amount of brake pumping to create a hard pedal while turned off. And I do emphasize small.

 

The pedal should be harder when the power booster isn't working, which is when the engine is off.

 

Yes it is much harder with the booster not running. We bled about 1+1/2 bottles of brake fluid out to really flush it and got as much air as possible out.