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Hi
Fixed my brakes In the 68 Gal but I can’t figure out how to get the brake system indicator light to go off again. Any ideas?
 

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have someone push on the brake pedal while you crack open awheel cylinder bleeder. if it doesent go out go tothe other end of the car and do the same thing. light is on because front or back failed, moving a shuttle over in the combo valve
 

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As stated above, you want to center a pressure differential valve. (See pic) Know that a very little amount of bleeding moves the valve.

>>>>>>Action
Inkedbrake valve_LI.jpg
 

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have someone push on the brake pedal while you crack open awheel cylinder bleeder. if it doesent go out go tothe other end of the car and do the same thing. light is on because front or back failed, moving a shuttle over in the combo valve
My son and I bled the brakes last night after replacing the rear wheel cylinders. We had bled the back passenger first as it was the furthest from the master cylinder and had next to no fluid in the line. We managed to get fluid running without bubbles throughout all of the lines. Would this not have accomplished this? We bled rear passenger, rear driver, front passenger, front driver in that order.
 

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That valve is very sensitive to pressure differences from front to back.
If the front to back is not equalized on the last bleeding the valve will shift to the weak side and stay there. Causing the light to be triggered.

The technique is to crack open the front or rear just enough to move the valve enough to shut off the light. NOT enough to move the valve all the way to the other side and turn the light on again. Light pressure on the brake pedal and just opening a bleeder valve is required. In addition you do not know which way the valve is set. So moving back and forth may be needed.

It can be frustrating as you move from front to rear and back again to get the valve centered and the light t9o go off.

>>>>Action
 

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That valve is very sensitive to pressure differences from front to back.
If the front to back is not equalized on the last bleeding the valve will shift to the weak side and stay there. Causing the light to be triggered.

The technique is to crack open the front or rear just enough to move the valve enough to shut off the light. NOT enough to move the valve all the way to the other side and turn the light on again. Light pressure on the brake pedal and just opening a bleeder valve is required. In addition you do not know which way the valve is set. So moving back and forth may be needed.

It can be frustrating as you move from front to rear and back again to get the valve centered and the light t9o go off.

>>>>Action
When you say “just opening a bleeder valve” do you mean just crack it and the shut it or actually bleed some fluid and if so how much? Also should it matter which wheel we bleed (drivers or passengers side)? This is frustrating. I just want to go for a drive! Thanks for your help.
 

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doesn't matter side .. only back- front. open the bleeder so fluid comes out. that will lower the pressure on the one you are working on. if it is the front you start with and the light doesn't go out, do the back.
 

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doesn't matter side .. only back- front. open the bleeder so fluid comes out. that will lower the pressure on the one you are working on. if it is the front you start with and the light doesn't go out, do the back.
Thanks. We’ve done this repeatedly and there has been no change at all. Not even a flicker on the light.
 

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Hi
Fixed my brakes In the 68 Gal but I can’t figure out how to get the brake system indicator light to go off again. Any ideas?
I went through all of this on my 78 F250 Ranger. I wound up having to replace the faulty proportion valve. Inside of that valve is rubber o-rings and a center body that floats back and forth to balance the brake pressure. 2 things on an old car that will make them fail: First an eroded o-ring inside may not be allowing the center of it to properly "float" where it should, so it thinks you have low pressure on one side or the other. Second is brake fluid, if not changed every so often, collects a lot of moisture. In an older car that hasn't had a fluid change since 1975 the brake fluid will be full of moisture (water). This moisture can corrode the inside parts in that valve making it stick.
 
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