72455

Was going take my '72 Supreme to work today, and when I turned the corner out of the court, the dash light came on for the brakes..uh oh. Made my way back to the house, and my brakes are working fine. My research here on CO is pointing me to the parking brake release switch. Question is, if I disconnect the switch and the light goes out, then it's the switch, right?

jaunty75

You're kidding, right?

72455

Um..no...why?

oldcutlass

First check the master cylinder and see if its full in both chambers. If the light goes out when you unplug the switch at the Ebrake then its not returning all the way or the switch is out of alignment or faulty.

jaunty75

If you disconnect the switch, you have broken the circuit, and the light will go out no matter what. What you need to do is test the switch itself. It's just a plunger-type switch like the kind that makes the brake lights go on when you step on the pedal. If the parking brake is released, that switch should not be pushed in, and the light should not be on. If it IS on, the first thing to check is to make sure the parking brake is fully released and that the plunger is actually fully out and not stuck in the pushed-in position. If the plunger is fully out and the light is still on, then you need to isolate the switch and put an Ohmmeter across the two leads. With the plunger pushed in, there should be zero resistance. With it out, there should be an open circuit (infinite resistance). If if doesn't pass this test, then the switch needs to be either repaired or replaced.

72455

So if it was fine yesterday when I drove it, and it was fine when I started it up this morning, is it a common occurrence for the switch to act up all of a sudden?

oldcutlass

Its a 47 year old car, nothing is normal.

72455

LOL...somehow I knew that would be the response 😀

72455

Checked it out...fluid level was good, didn't have any leaks. Gave the parking brake pedal a slight tug and hit the key. Light was out, so I'm guessing it was the switch but I'll keep an eye on it. Thanks to all who helped.

oldcutlass

Lubricate the pivot points and the cable.

72455

The pivot points for the pedal?

oldcutlass

Yes

TripDeuces

Is it nothing more then the emergency brake pedal pushing on its switch? Grab the e-brake pad and pull it toward you while holding the brake release.