Help! Brake lights stuck on
Help! Brake lights stuck on I'm in the process of installing new upper and lower A Arms and I removed the brake master cylinder(did not open any lines just moved it out of the way) to get that torque bolt under it. And noticed my brake lights are stuck on. So I reinstalled the master pressed the brake pedal and I have no brake pressure and lights still on.? Is this a vacuum problem or need to bleed the brakes? The booster piston is all the way depressed. Does this need adjustment?
Staging Lane
Joined: Sep 2010
Posts: 93
Likes: 0
When you moved the master cylinder, the brake system may have somehow lost pressure and the brake pedal fell to the floor - turning the brake lights on. Sounds like you need to bleed the brakes and if that doesn't work then proceed with other work - may have to bleed the master cylinder, abs...
Last edited by NeoLoco; Jul 21, 2020 at 03:42 PM.
Ok so I found my issue. When I removed the master cylinder that front piece of the brake booster fell off. I replaced it with another brake booster seemed pretty straight forward 4 bolts and brake pedal link..... Now my pedal is stiff as hell and brake lights are still stuck on. I'm assuming it's not getting vacuum I checked the vacuum hose it's good. Brake lines were never cracked open. Would bleeding brakes still be an option?
Staging Lane
Joined: Sep 2010
Posts: 93
Likes: 0
Sounds like an issue with the brake booster with the hard pedal, and an issue with the pedal or brake light adjustment for the brake lights. There's a procedure for installing a new brake booster. I'd get the exact procedure. Basically after you've installed it if you still have a hard brake with the engine running then there may be an issue with the vacuum line to the booster leaking, a vacuum leak somewhere else -causing the booster to not get enough vacuum, the check valve in the line is broken, or a problem with the brake booster.
There's a plunger switch mounted to the pedal assembly that actuates the brake lights. This switch is adjustable. The brake pedal may have changed positions with your repairs and be on that switch all the time.
Once you are sure your brakes are working like you want them, you should be able to remove the plunger switch and adjust the screw mount to get it at the right contact point.
Once you are sure your brakes are working like you want them, you should be able to remove the plunger switch and adjust the screw mount to get it at the right contact point.
