1999 Brake Problem with Warning light "P!"

Hello,

My wife was driving her 1999 jeep xj today and had to stop hard. After she stopped the brake warning light came on and is staying on, It reads "P!".

Now she has to begin stopping sooner and there seems to be more brake travel.

I added brake fluid but the light still is on and the brakes did not get better.

The jeep has 158,000 miles on it, and the rear brakes are still orginal, I have only had to replace the front brake pads and rotors when needed, but the backs are still from the factory.

I am only making a guess but could it be the wheel cylinder piston, I read it here on the forum.

Thank you for any help..

Jackate

Ok, big secret, but I am going to share it with you--brakes are a maintenance item, and need to be inspected and serviced on a regular basis, and 158K miles is NOT an approved maintenance interval. :twak:

If you are loosing fluid, something is leaking. If you had to add fluid, then there is a leak OR the pads/shoes have become so worn down that the wheel cylinders/calipers have to travel a greater distance, so the level in the reservoir drops. :lecture:

Either way, you need to increase the life insurance policy on your wife--or fix the brakes, and I recommend the latter.

I recommend you take it to a reputable shop--call around and get estimates. You can expect to be paying for more than just pads and shoes, from the sound of things.

The front brakes do 80 percent of the braking, And I have serviced them many times.

The back brakes have never been a problem.

Now I will replace them and check for leaks.

I don't trust to many mechanic's touching my vehicle and that's why I have had hardly any problems in 11 years.

Same with my 2005 Scion TC with 114,000 miles, I have only had to put in a 50 dollar water pump, brake pads, rotors, and tires.

Doesn't the P light come on for "Parking Brake"?

Yep, but also comes on for low brake fluid as Mr. Peters alluded to.

jackate said:

The front brakes do 80 percent of the braking, And I have serviced them many times.

The back brakes have never been a problem.

Now I will replace them and check for leaks.

I don't trust to many mechanic's touching my vehicle and that's why I have had hardly any problems in 11 years.

Same with my 2005 Scion TC with 114,000 miles, I have only had to put in a 50 dollar water pump, brake pads, rotors, and tires.

Click to expand...

Good for you! Don't forget that brake fluid absorbs water and should be changed every two years or so. This helps keep the brake pistons, etc. from rusting up.

FWIW, I haven't posted this in a while so here is my free brake advice. Hopefully it helps.

So, #1, you make sure there are no signs of leakage. That means no use of brake fluid from the reservoir. And no wetness on the inside of the rear wheels, brake lines, etc. If there is leakage, fix that first. #2, start vehicle and pump up brakes about 5-10 times and hole down pedal hard. If it goes down steadily, your master cylinder is shot - replace. Only two things can make the pedal go down. External leaks or internal master cylinder leaks. If it holds, and you still need to pump the brakes to make them work, either your rear brakes are way out of adjustment or you have air in the lines.

Adjusting rear brakes: They are supposed to be self adjusting, but that shit freezes up quite a bit, and even after I fixed mine, it seemed like the original self adjusting cable was made too long to adjust properly. The best is to take all this stuff apart (pull the drums off and lube it all up including dia-assembling the adjuster star wheel). But, thru the slots, you can tighten up the free play in the rear brakes which could be taking up more fluid than the stroke of the master cyl can displace. If you never did it before, you probably need to pop off the rear drums and look at everything.

Bleeding brakes: The best way is the GRAVITY method. The only problem is it takes a lot of beer and you don't want to drive right after. (CAUTION: YOU MUST BE 21 TO BLEED YOUR BRAKES THIS WAY!) I use it whenever I replace brake cylinders or calipers, but mostly it's just to change the brake fluid, which I do whenever I change shoes or pads. Ideally you change brake fluid at least every other year. If you worked on old cars and saw rusty pistons, you'd know why, but people also say that old brake fluid boils and won't stop you right.

1.) Get the car in a position where you can open up the bleeders. I always like to break them loose with a 6 point socket being careful not to break them off. If you can, spray them with breakaway or similar a day before.)
2) Starting with the bleeder furthest away from the master (pass. rear), open it about 1 turn. You can put a little hose and cup on it if you want to keep the old fluid from running all over. Make SURE to keep the master cylinder topped off with fluid and DON'T let it get down to where air gets back into the master cyl. Let it flow this way until the fluid comes out of the bleeder clean. This will take at least 2 cups or so of brake fluid. Using gravity alone, you can drink 2 beers while topping off the master cylinder for the first corner. (CAUTION: Do not store brake fluid in beer cans or put beer into master cylinder. Drinking a little brake fluid however will probably not kill you. Beer in your brake lines might.) Snug up bleeder good when you're done.
3.) Proceed to drivers rear and repeat. It won't take as long because the long brake line has already been purged of the old fluid. So you have to drink your beer faster.
4.) Pass front. Drink even faster.
5.) Drivers front. Etc.

Patience can be substituted for beers, but that's no fun.

This prevents the rubber pieces from going any further than they are used to and self destructing.
:cheers:

Thanks for the reply Winterbeater and others,

You have given me alot of good information! I am going to take it to a Mechanic this time in Paterson N.J. that does good work at fair prices, because it is so cold here and my garage is not heated.

Wow my brake fluid is original almost 11 years old.

I have a friend who works in a parts store that supplies other parts stores ect, so I can get the parts at a good price.

I will follow the methods you gave so I will know what went wrong, If it is the master clylinder or an external leak.

I am going to buy all the parts I need for replacing the rear brakes since the are orginal from the factory.

List
Brake shoes
Brake hardware kit
Brake spring kit
dot 3 brake fluid

How do I know if I need new Drums?

Thanks again for all your help, If anyone knows what other parts I should buy please let me know, I get them at a good price so I hope I have not left to much out.


Thanks again
Have a good night

Find a job you love and you will never work again! Wish I could find that job..

If the drums are gouged, they should be turned (lathe). There is a maximum size that they can be machined out too. The machine shop will measure them. If it stops unevenly now, you would want to have them checked or turned.

Thanks all,

I took it to the Mechanic and he replaced the rear brakes and rear cylinders. He also checked the front brakes and whole brake system.

I needed a new water pump also, it was rattling.

He did everything for $310.00, the brakes, water pump and new fluid.

I thought that was a good deal because it's cold here and I did not feel like working on it.

not bad though, 157,800 miles on orginal rear brakes, the drums still had those little metal washers they put on when it was on the asembly line to keep the drums from falling off as it went down the line.


Thanks
Jackate

jackate said:

Thanks all,

I took it to the Mechanic and he replaced the rear brakes and rear cylinders. He also checked the front brakes and whole brake system.

I needed a new water pump also, it was rattling.

He did everything for $310.00, the brakes, water pump and new fluid.

Click to expand...

$310 is a reasonable price for these services.