Hi everyone,
So I was out on the road a couple weeks ago, and all of a sudden it felt like there was something stuck under my brake pedal! I managed to e-brake and pull over, but when I looked there was nothing there. Eventually I managed to determine that the brakes aren't stuck, it's simply really difficult to press the pedal; I think the brake assist is at fault.
I've been reading that the hydraulic brake assist of the late 80s models is unreliable, but this car has the electric brake assist. Has anyone experienced this before? I can't tell if the issue would be something pneumatic, or an electrical mishap (the car doesn't love the rain). Would anyone know if the whole assembly has to be replaced, or if something commonly goes wrong?
Thanks!

 

If you have a hard pedal this usually means the nitrogen filled sphere has lost its charge and needs to be replaced.

Check the archives for instructions on how to test and possible sources for aftermarket replacements.

 

I finally got the replacement accumulator (one of the aftermarket GM ones, fits perfectly), and unfortunately that wasn't the issue. The pedal is still rock hard (though I'm sure the accumulator needed replacing anyways).
There are no warning lights or anything. Could the pump motor be fried, is that a common issue?
When I worked on the ignition system there was a diagnostic guide for voltage testing etc.; does anyone know of such a thing for the brakes?
Would appreciate any further insights! Thanks.

 

Pressure switch/circuit and/or pump motor failure.
Check relays and fuses first?