The rear brake light is dim unless you put full pressure on pedal. this is only for rear pedal ,front is fine

Brake booster

Pedal, not peddle. First make sure reservoir is full at the brake master cylinder. Then check your brake pads (for disc brakes) and/or brake shoes (for drum brakes). When the pads or shoes are very worn down, you will get a low pedal. If you have disc brakes on the front and drums on the rear wheels, first try just replacing the front brake pads. If you get a good pedal after the front is done, many people tend to let the rear brake shoes go unless they are making noise. These systems are designed to put most of the braking force on the front discs, so the rear shoes do not need changing as often.

It sounds like the rear brake pressure switch is bad. The wires for the front brake light switch are wired in parallel to the this switch. Replace the pressure switch in the metal brake line coming from the rear brake master cylinder going to the rear brake caliper.

Good Luck
Steve

Hi, bleeding your rear brakes with engine running, you should get enough pressure out of the lines to squirt 3-4 feet. In other words, good pressure. If all you get is a trickle, you probably have a bad master cylinder. Just because its full of fluid, does not mean the seals arent shot. If you have bled them in order, left rear,right rear,left front,right fornt and have bled them enough to get fresh fluid out of each one without achieving good solid pressure at all wheels, replace your master cylinder. There is a proportioning valve, but usually it will affect only one wheel when going out, usually the left rear.
Brake pedal height comes from the rear brakes, so if you have bad pressure there, you will never get a good pedal. Eventually with a bad master, your brakes will go completly out..Mike

If your brake light is staying on, it's due to one of the two switches are made. You have one switch for the front brake and one for the rear brake. It could be either switch making the light stay on.

Odds are it's the front brake switch. Start off by making sure the front brake master cylinder assembly is tight against the throttle assembly switch housing. Loosen the bolts that hold either the master cylinder or the throttle switch housing and move the two assemblies as close together as possible.

If this doesn't work, you will need a DVOM (digital volt ohm meter) to test the switches. Test the rear brake switch first as it's the easiest to get to. Remove the wires from the switch, put your DVOM in the lowest resistance range you have. Touch the probes of the meter to the brake switch wire connections. With no pressure on the rear brake pedal, you should show no continuity, infinite ohms. When you depress the pedal, you do show continuity, zero ohms. If this checks correctly, the front switch is the culprit.

If you show continuity or zero ohms and the rear pedal is not depressed, you could have problems with the rear master cylinder not bleeding the pressure off the rear brake. Loosen the brake line right where it comes out of the rear master cylinder and see if the light goes out. If so, your rear master cylinder needs rebuilding.

do you have a self bleeder kit? first off, you have to bleed the master cyl back into its self and the combination valve before you go to the wheels. when you do that, I think you will find that you have air in the lines. disconnect both brake lines from the master cyl and put the bleeder kit fittings on the master cyl, then put the rubber tubing with the kit on the fittings and submerge it in the brake reservoir. make sure its full. then pump the pedal until you get a hard pedal. if that is the case, reconnect the lines to the master, then have an assistant pump up the brake pedal with the engine off, and bleed the combination valve which should be connected to the master by steel tubing. pump it up, then hold it down, and crack the fittings loose, one at a time until the pedal goes about half way down, but do not release the brake pedal until the line is tight again, otherwise you will **** air in the lines. after you do all that, go to the farthest caliper or wheel cylynder from the master and bleed that with the same technique,and dont release the pedal until you close the bleeder screw. unless you have a major prob, this will work.

to do a complete job. you need to bleed all 4 wheels, starting from Right Rear. Right front. Left Rear. Left Front.

you still air in system or a bad master cylinder or brake booster.

Have you checked the hardware on the disc brakes all the way around, as well as checking the rear pads? Wore out hardware could cause you to require more pressure to get the pads to move, as well as low brakes on the rear. Your braking system sends more pressure to the front of the vehicle because it requires more pressure up there. Less pressure on the rear can cause this to happen. I'm willing to bet the problem from the pedal is coming from the rear brakes somewhere and not the front. The last possibility that I can think if is a problem in the ABS solonoids, they might not be opening up all the way causing you to require more pressure.