Maymyvetteliveforevr

When the brake light is on in the dash, does it mean that it's only related to the emergency brake? I ask since I don't see any sensor anywhere from the master, brake booster, lines caliper etc. The only sensor/switch I see is at the e-brake as well as brake pedal, but I assume that's related to the "brake Lights".

My brake light is on, I've installed new lines as well as all new e-brake system including e-brake pads and can not get the light to turn off even after bleeding twice. Mind you my pedal is still spongy and I'm using Dot 5 fluid.

I always check the light when the car is running, or do I only need to turn the ignition on?

I guess it's more than one question.


Thanks

0Willcox Corvette

It could be on from the pressure switch on the proportioning valve or the ebrake handle. I'm guessing you still have air in the system if you have a spongy pedal.

Willcox

65GGvert

Wonder what year it is. Wonder if it's power brakes.
The brake light indicates that either the parking brake is on, or the pressure is greater in either the front or back brakes system. You can tell which it is by disconnecting the wire from the parking brake switch and see if the light goes out. If the pedal is spongy, it's probably the second.

Maymyvetteliveforevr

Willcox Corvette - Thank you for the reply. I would agree that must still have air in the brakes. I've always had more problems getting the air out with Dot 5 silicone brake fluid.

As for the pressure switch on the proportioning valve, since it's no electrical, how would that trigger the brake light?


The e-brake has been adjusted so I'll assume it may also need an adjustment to the e-brake light switch.


Am I to assume then that the regular power brakes can activate the dash brake light? If so where is the electronics to sense/activate the light?


65GGvertThanks for the reply, it's a '75 Coupe with power brakes. If I may ask the question again, where is the electronics located to activate the regular brakes, not the e-brake?

Richard454

It's a single wire tan colored that is triggered to ground- if you disconnect it- and the light goes out- there's where your problem lies-



This is on a 78 pace car-

Maymyvetteliveforevr

Richard454- Thanks for the reply and information about the tan wire. I checked and the tan wire was not connected so I did connect it and there is no change. The brake light stays on whether the wire is connected or not.

I now know where the brakes light get's it's signal from, the e-brake switch and the tan wire from the proportioning valve.

I'll try to bleed the brakes for the 3rd time, going from the furthest way (passenger rear, drivers rear, passenger front, drivers front. The rear brakes I bleed all three screws from the top down and the fronts only have one bleeder.............correct?

Does the engine need to be running or just the ignition switch to the on position to check for the brake light to go off. I would imagine just the ignition has to be on since vacuum to the booster shouldn't affect brake fluid pressure.

tracdogg2

Only the two upper bleeders on the rear calipers. If you have a third bleeder down low, don't open it. Someone put a bleeder in there instead of the correct plug.

Richard454

The ignition needs to be on-

If the tan wire is disconnected at the valve under the hood-then the wire is either seeing a ground at the parking brake handle or it could be shorted somewhere.

See the black switch- w/ the spring around it- check that as "65GGvert" said.

Maymyvetteliveforevr

tracdogg2, thanks for the reply, I bleed the brakes again, this time not touching the bottom bleeder and the light is still on.

Richard454hanks for the reply, I checked the switch at the e-brake handle and it's adjusted properly. I'll try to bleed the brakes again tomorrow for the 5 time.

Moose 02 FB

can't seem to find it but there is a procedure to reset the balance on the balance pressure switch. but if your brakes are spongy you do still have air. do you know anyone with a pressure bleeder that may save you hours of trying to get the air out.

i also put a hose on the caliper and just let it drip and did get some of the air out just make sure you keep an eye on the fluid in the mc you dont want it to go dry.

another thing to try is to wedge the brake pedal down with something and leave the cover off the master cylinder overnight sometimes it will back bleed and the air will float to the top.

the air in the system and the wire off the balance switch may be separate problems if the wire was off and the light still on

Richard454

Brake light-

If it is still on- and you have disconnected the tan wire at the proportioning valve and the e-brake handle is completely down (actually push on it)- then you have a short somewhere in the wires.

Maymyvetteliveforevr

Thank you for your help the problem is solved.


For some reason the brown wire came out of the e-brake switch when I was putting the cover back on and when I connected the brown wire to the proportioning valve I assumed it was still connected at the e-brake switch. It pays to double check your work.


Thanks again

As for the spongy brakes I wonder if its due to the pads being soaked in brake fluid due to 5 brake bleeds. I did do a light sand before installing the pads but I guess it maybe in deeper than I thought.

lionelhutz

Spongy brakes is probably due to the DOT5. If you aren't very careful with the handling and bleeding then you end up with entrained air.