Topic: Parking Brake Light
in Forum: C3 Handling Components
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My 1969 parking brake light on the instrument panel will not go out. When you pull up on the handle the light gets brighter. I do not notice any dragging or noise from the brakes. I checked the master cylinder and the front half was full of fluid and the back half was 1/2 full. I filled up the rear half and drove car again. The light stayed on. Brakes feel good, pedal is firm. Any suggestions?
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It sounds like the light is being turned on by the proportioning valve, not sure of location on the 69 it should be a gold looking block where the rear and front brake lines meet. it sets when their is unequal pressure between front and rear brakes. you may have a leak in the rear. if the brake pedal feels good you might try giving a hard quick push on the break pedal to get it to reset.
Bob is right on. You also may try bleeding the brakes in sequence (rear first, then front), then pressing the brake pedal hard for a few seconds.
I'd guess you have a leak somewhere in the rear, like Bob mentioned (either a caliper or a line). The light getting brighter is the switch under the parking brake, it provides the ground for the light bulb. The prop valve switch does the same thing. That's telling me you have two sources of ground for the light bulb circuit: one from the proportioning valve, the other from the eBrake switch.
Best of luck.
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|UPDATED|2/10/2013 8:24:20 AM (AZT)|/UPDATED|
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Or....it could be the wiring has a short in it somewhere. Disconnect the wire at the proportioning valve, and see if the light goes out. If it does, the problem is with the p-valve. Either it has flipped to one side, or it is shorted internally.
If the light does not go out, the problem is elsewhere. Could even be the p-brake switch itself. Disconnect that, and see what happens. If you have both the p-brake switch and the p-valve disconnected, and the light stays on, then you'll need to dig into the wiring.
If the light does not go out, the problem is elsewhere. Could even be the p-brake switch itself. Disconnect that, and see what happens. If you have both the p-brake switch and the p-valve disconnected, and the light stays on, then you'll need to dig into the wiring.
Joel Adams
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I will check into the wire connection and try to isolate the problem. If I need to bleed the system I will let my mechanic do the job. I have heard that bleeding the brakes on the C3 is not easy.
Update on the repairs. The master cylinder did have a leak. It was replaced last week. Drove car home from shop and everything worked normal. Drove car today and at first the light was out. The light came back on after driving the car a few miles. Same indication. light on all the time. If you pull up on the brake handle the light get brighter. Maybe that valve or wiring??
in Forum: C3 Handling Components
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