I am working on a Crown FC 4000 it has a pulsating noise in the brake system. With the unit powered up there is a pulsating noise and it can be felt in the two metal tubes that run from the park brake valve to the brake pump and the other to the accumulator. When the park brake is released the pulsating increases. When the brake pedal is depressed about half way an alarm sounds, pedal will drop to the floor plate and the pulsating will increase.
thank you in advance for any help I can get on this.