brake problems..(warning light)

-
fredsmedina

fredsmedina

6 Dart 7 MOPAR OR NOCAR
Joined
Aug 29, 2009
Messages
880
Reaction score
2
Location
Sacramento / Elk Grove CA
In my '73 satellite, ever since I bought it(2 months or so ago), the parking brake warning light has been on.. I replaced the master cylinder and had a power flush done. So all brand new fluid in there..

What reasons are there that the brake light could be on? I'm thinking possibly it has something to do with a vacuum line or something?

Every once in a while, while I press down on the brake pedal, I'll see the light turn off for a quick second.

The brakes still feel very firm, and I can stop with no problem. Every once in a while though, the pedal will go down a litle further than it should IMO. It neve bottoms out though..

Oh and I have Power Brakes, disk front and drum rear..

All suggestions are helpful! thanks
 
From what I remember the warning light can be lit from 2 places.
1. The switch on the parking brake lever.
2. The wire running to the proportioning valve.
From what you describe of the issue, it might be the prop valve. When you push down on the pedal, the valve is trying to move..that's why the light will flicker...now where did I put that "how to reset the proportioning valve" doc...hopefully someone will have the procedure, cause there's no way I'll find it now that it's needed :lol:
 
player1up said:
From what I remember the warning light can be lit from 2 places.
1. The switch on the parking brake lever.
2. The wire running to the proportioning valve.
From what you describe of the issue, it might be the prop valve. When you push down on the pedal, the valve is trying to move..that's why the light will flicker...now where did I put that "how to reset the proportioning valve" doc...hopefully someone will have the procedure, cause there's no way I'll find it now that it's needed :lol:
Click to expand...


lol. okay well thanks for that info! hopefully somebody has that procedure
 
There may be something I'm overlooking, but I believe that a serviceable proportioning valve should center itself when the system pressures are correct. I'd probably bleed the system (note: vacuum bleeders are worth the $30 just in preventing messes) and see if everything becomes happy.
 
doktor_x said:
There may be something I'm overlooking, but I believe that a serviceable proportioning valve should center itself when the system pressures are correct. I'd probably bleed the system (note: vacuum bleeders are worth the $30 just in preventing messes) and see if everything becomes happy.
Click to expand...

I just power flushed the whole system. didn't fix a thing :???:
 
tedsweet said:
parking brake peddle?
Click to expand...

nope. parking brake pedal comes all of the way out and disengaged, but light stays on..

someone told me it could be a bad/broken/loose pedal return switch..i'll have to look into that. but every once in a while, the pedal will go down too far, and the brakes dont feel as strong as they're supposed too..

which is sorta leading me to think that maybe there really is some sort of "problem"
 
Still no luck finding the reset procedure, but I think that it should recenter if the brakes are bled in the correct order PR,DR,PF,DF unless it's stuck. Maybe the reman master is the problem...had one right out of the box that would "leak down" (internal leak), would feel kinda spongy and if you held it at a certain point it would leak down. Might still be air somewhere.
 
player1up said:
Still no luck finding the reset procedure, but I think that it should recenter if the brakes are bled in the correct order PR,DR,PF,DF unless it's stuck. Maybe the reman master is the problem...had one right out of the box that would "leak down" (internal leak), would feel kinda spongy and if you held it at a certain point it would leak down. Might still be air somewhere.
Click to expand...

alright. well hopefully the master isn't my problem. any idea how i'd know if it did have an internal leak? because if you hold the pedal at a certain point, the pedal will "loose pressure" meaning my foot will just keep going down.
 
Look for a blown wheel cylinder or a leak in the master cylinder. On a disc set-up, look for fluid around the caliper pistons. It could also be a bad hose or a loose connection. You are definitely losing hydraulic pressure if your pedal won`t hold in one place when compressed.
 
fredsmedina said:
alright. any idea how i'd know if it did have an internal leak? because if you hold the pedal at a certain point, the pedal will "loose pressure" meaning my foot will just keep going down.
Click to expand...

You just answered your own question. Its the master cylinder. Or a slight possiblilty like longgone has said. But a leak should be very visible if it is leaking/loosing pressure that fast.
 
thanks guys..looks like i'll need to be replacing that. dam it..hopefuly its under warranty because i just replaced the master a couple weeks ago. I've searched for a leak though and cant find one.

i'll check for fluid around the caliper pistons though..
but i keep checking fluid level in the master, and its not going down at all as far as i can tell..
 
If your brake pedal goes down while you're holding your foot on it then your secondary piston in the master cylinder is bad and needs replacing. Go get a rebuilt master or rebuild it yourself.
 
I thought you could STOMP on the brake pedal like 3 times and that would "sometimes" free up the proportioning valve.
 
cudajim said:
If your brake pedal goes down while you're holding your foot on it then your secondary piston in the master cylinder is bad and needs replacing. Go get a rebuilt master or rebuild it yourself.
Click to expand...
can the 2nd piston be bad already?! i just bought this master..its remanufactured..
 
Is the wire on the prop. valve the ground right? so if i take that off, and the light turns off, then I know that the prop valve is my problem? or is that incorrecct?
 
fredsmedina said:
Is the wire on the prop. valve the ground right? so if i take that off, and the light turns off, then I know that the prop valve is my problem? or is that incorrecct?
Click to expand...
It is a switched ground circuit. If the light goes off when you yank the wire, that would indicate that the light is being triggered by the switch. Could be a defective proportioning valve, but more likely it's working correctly to flag a pressure issue (master cylinder, bubble, etc) as also indicated by the occasional pedal creep.
 
doktor_x said:
It is a switched ground circuit. If the light goes off when you yank the wire, that would indicate that the light is being triggered by the switch. Could be a defective proportioning valve, but more likely it's working correctly to flag a pressure issue (master cylinder, bubble, etc) as also indicated by the occasional pedal creep.
Click to expand...

well my dad drove my satellite today, and said that the pedal isn't "creeping" at all and that its fine.. so i'm on my way outside with a flashlight right now to disconnect that wire and see what happens.. i'd rather replace the master than the prop valve probably. but we'll see..
 
it is a pressure differential switch, it is designed to sense an imbalance between the front and rear brakes, the switch needs to be centered in order for the light to go out, after you replace the master cylinder and bleed the brakes, have someone open one of the bleeders (front of you bled the back last) and very gently press the brake peddle until the light goes out, if you go to far or nothing happens go to the other end of the car (back to front not right to left) and try again
 
when i disconnected the ground from the prop valve, the light turned off! so this definitely means that my problem is the prop valve?

also though, with the wire from the prop valve unplugged, when i put on the emergency brake, the light doesn't turn on. what does this mean?
 
sounds like the "ball" inside the proportional valve is stuck to one side due to a pressure imbalance between front and back brakes as was stated earlier.
 
You must log in or register to reply here.
-

Back
Top