As title says my rear brake won,t pressurise i,ve bled the system so i know its not that i have really pump the brake pedal to make the piston move a tiny bit at a time and when it reaches the pads it has no power to push on them just wanted to now if i,m in the right area in my potential diagnosis thanks
I had an issue with bleeding. Always thought it was bled but it was blocked air bubbles. I removed caliper and shook it and then re bled and could see it was trapped air.
there just is not any pressure the brake pedal does not firm up at all if the piston was stuck i would still feel the pressure build as i try to pump the brake. If the master cylinder is not forcing enough oil into the the brake line without enough pressure it would fail to push the piston with enough force to push against the pads