Hard Brakes

[87TurboTATL]

Guys I need some trouble shooting help. My brake light is on and stays on. I replaced the Accumulator and the light is still on and the brakes are still hard. I need some help!!!

Thanks

 

[salvageV6]

Check the powermaster fuse.

Do you hear the motor/pump running?

 

[87TurboTATL]

I checked the fuse and changed it. It wasnt blown but looked worn. I still dont hear the motor/pump running. I hope that I dont have to replace the entire unit. Anything that you can think of?

Thanks

 

[Fast87Buick]

If the pump is bad I think it can be replaced separately, there was a guy selling these rebuilt a few years back. The whole powermaster unit can be replaced, I did mine a few years ago. Kirbans is about the only source for these now that I know of. Kirban also sells a manual about the powermaster brake unit which is pretty good. or You can convert to vacuum boosted brakes like a lot of guys have. Just do research on here or gnttype.org and you'll find what you need.

 

[TurboBuRick]

Could be the switch on top went bad.

 

[Fast87Buick]

Could be the switch on top went bad.

I didn't remember that, check the easy things first!

 

[87TurboTATL]

Thanks I will try the switch first.

 

[salvageV6]

Just jump the A + C terminals on the switch to test it, pump should run when the black and Wht. wire are shorted together, or the white wire goes to a good ground.

Black wire should be a good ground read with an ohm meter to battery ground, low ohms.

Make sure the 5A relays fuse is good and working, Brown wire Pin B of the powermaster wire connector should be +12 when IGN is in RUN position.

Pin A the black wire of that connector should be a good ground and is the ground to run the motor.

Pin C the Red wire should be +12 at all times and is the hot for the motor.

Internal relay will activate when the IGN is in RUN and the white wire is shorted to ground simulating the brake pressure switch calling for more psi.

Several tests to do before buying and swapping the switch, unless you have a spare handy then a quick swap is easy.

Make sure the +12 signals are correct too.