DodgeIntrepid.Net Forums banner

brake lights on after replacing power booster

18K views 9 replies 3 participants last post by  msmcintosh 
#1 · (Edited)
After I replaced the power booster for the brakes, the booster does not allow the brake pedal to travel back far enough to depress the brake light switch. So now the brake lights are always on. The brake pedal is about 4 pennies short of depressing the switch in far enough to turn off the brake lights.

I'm not sure how to fix this, other than to glue the pennies to the tab on the brake pedal. Any one else ever had a problem like this? Any suggestion for fixing it?

Thanks

The plunger on the brake light switch is ratcheted and needs to be pulled out until it stops. It took some force with a wrench to get it pulled out. When the switch is placed back it's bracket, the brake pedal will push the plunger back in to where it needs to be.
 
#4 ·
I believe the booster has an adjustable shaft on it. Did you Check the old vs New?
 
#5 ·
The plunger on the brake light switch is ratcheted and needs to be pulled out until it stops. It will extend approximately 3/4 of an inch. It took some force with pliers to get it pulled out. When the switch is placed back it's bracket, with the brake pedal depressed as far as it will go, releasing the brake pedal will push the plunger back in to where it needs to be. The ratcheting mechanism hold the adjustment.

There's no adjustment on the booster.
 
#7 · (Edited)
Front brakes locked

There's a big problem. After I drive the car about 3 miles, the brakes begin to lock up. They lock up badly enough that I have to floor the car to get it to move. The travel in the brake pedal goes to near zero. The vacuum hose looks OK. Some of the brake pads have stuck to the rotors and smell burnt.

From what I've read I need to take the master cylinder off to adjust the rod. It says that there needs to be an .020" gap between the rod and the master cylinder. I'm not sure how to measure the gap. Maybe this is why my brakes are locking up?

I unbolted the master cylinder from the power booster and I don't see any way to adjust the rod.

Update - I gave up and brought the car to my local shop. They informed me that I need a new master cylinder, front calipers and rotors. Only the front brakes lock up. They told me the intense friction destroyed the calipers and rotors. I actually think they are salvageable, but they wouldn't warrant their work unless I had them replaced. I don't know how changing the power booster could cause these problems. They haven't done the work yet.
 

Attachments

#8 ·
i think its the problem of your brake booster pedals become hard and brakes will jam if booster is not working properly check you replaced the booster correctly.And to confirm it if the lock up happen again when you run 3 miles kill the engine for few minutes and run again check whether the problem persist.so its definitely booster problem no need to replace MC.the barke pad and rotor replacement depends upon your present condition of them
 
#9 · (Edited)
I think you're right about the problem being the booster, especially since the brakes worked before I replaced it. I think the rod is a little too long. The booster was supposed to not require any adjustments according to the manufacturer.

I drove the car about 4 miles to get something to eat. Everything seemed OK. Shortly after I left, the brakes locked up. I drove about a mile, then stopped and shut off the car. When I started off again, the brakes locked up. I wanted to get home, so I just stepped on the gas to get home. A couple of miles from the house, it seemed to get much better.

The shop replaced the master cylinder, calipers and rotors. When they took the car for a test drive, the brakes once again locked up and they had to tow it back to the shop. More than likely, I believe, there was nothing wrong with the original master cylinder.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top