PARKING BRAKE MALFUNCTIONS PARKING BRAKE MALFUNCTIONS 2) 2) 4-38 Problem Cause Remedy Brakes chatter Air in brake system. Worn brake surface material. Wrong oil in differential. Do brake bleed procedure. Inspect brake surface material. Drain.Refill. Hissing noise when brake pedal is held with engine stopped Leakage in brake valve, or brake piston. Do brake system leakage test. Brake pressure warning light will not go out or stays on excessively long after start-up Malfunction in brake low pressure warning switch. Brake accumulator pressure too low. Low brake pump standby pressure setting. Leakage in pressure reducing manifold block. Leakage in brake system. Worn brake pump.
Leakage in parking brake solenoid. Replace switch. Recharge accumulator. Do brake pump standby pressure test. Do pressure reducing valve manifold leakage test. Do brake system components leakage tests. Do brake pump flow test. Do parking brake pressure test. Problem Cause Remedy Brake will not hold Pads not adjusted correctly. Malfunctioning parking brake solenoid. Worn brake disk and / or brake pads. Brake piston hangs up in bore. Adjust parking brake. Inspect and replace. Disassemble, inspect, repair. Remove and inspect. Repair. Brake disk overheats Pads out of adjustment. Brake not released. Adjust parking brake. Release parking brake. Disassemble, inspect brake. Repair if necessary.
Inspect for loosen or broken lines between brake pressure switch and indicator on dash. Parking brake indicator in monitor does not come on when brake applied Faulty wiring or switch. Inspect for loose or broken lines between brake pressure switch and indicator on dash. Inspect for a faulty indicator on dash. Replace if necessary. Brake will not apply Pads out of adjustment. Malfunctioning wiring, switch, or solenoid. Restriction between brake valve and brake. Adjust parking brake. Check electric circuit. Remove hose and inspect. Replace.