View Full Version : ABS Woes, still.

08-03-2010, 11:54 AM
After reviving the car from storage and the 95 supercharger/FMIC install on my 89, I have no brakes. The pedal is rock hard, but no lights show up on dash. The self test 4 second yellow light doesnot ever come on, the red on only when e brake applied. I also upgraded to newer spindles, and have no ABS sensors connected in front, and removed actuators from firm ride suspension if this may have anything to do with it. I just replaced the pump motor relay with no luck. No idea where to go next. Anyone???.....

08-03-2010, 12:22 PM
Sounds like the pump motor may be locked up....

This happens a lot when these cars sit for long periods of time.....

Pull the connector to the pump motor and see if you are getting power to the motor.....

08-03-2010, 12:24 PM
as soon as i get home i will. any way to get it to "unlock"? tapping it or anything? if it needs replaced looks like another year without my bird:(

08-03-2010, 04:53 PM
Ok- no power at connector across any of the pins. Fuses are all good under hood and dash, new relay put in, so could it be the pressure switch? How can I check it?

08-03-2010, 08:12 PM
See if you can apply 12v power directly to the pump motor.....

Pressure switch could be stuck in the closed position....

08-22-2013, 04:44 PM
Mine is doing same thing. Motor does not run and not getting power to the plug. Wires are gray (4) two of them have a red stripe. Pressure switch keeping power from the motor? If I apply power to the motor plug, would it be to the wire with the red stripe?

08-22-2013, 07:16 PM
You are correct, the red striped wire is the hot wire....

But for testing purposes, it doesn't matter which wire is which.....

It's a DC motor, which means if you hook it up wrong it will run backwards (CCW)....

the purpose of this test is to verify if the pump motor is locked up.....

If you apply power to it and it spins, the problem is either the pressure switch, pump motor relay, or ignition switch....

08-22-2013, 07:50 PM
Thanks Ed. I get power to the relay and all fuses are good. I will check to see if pressure switch is the culprit.
Where can a new switch be purchased if that is the problem?

08-22-2013, 07:59 PM
Great article on the early ABS system.


08-23-2013, 04:10 PM
I believe that GM still stocks the pressure switch as well as Saab....

08-24-2013, 01:34 PM
I have a brand new one I bought from a fellow member. My rebuilt abs worked for 5 mins then the only non replaceable part,(abs pump), died. $100 shipped..