2. TROUBLESHOOTING 2. TROUBLESHOOTING 1) 1) SERVICE BRAKE SERVICE BRAKE Diagnose malfunction charts are arranged from most probable and simplest to verify, to least likely, more difficult to verify. Remember the following steps when troubleshooting a problem : Step 1. Operational check out procedure (see section 1) Step 2. Operational checks (in this group) Step 3. Troubleshooting Step 4. Tests and adjustments (see group 3) 4-37 Problem Cause Remedy Poor or no brakes Brake accumulator charge low. Brake pump standby pressure low. Brake pressure low. Air in system. Worn brake surface material. Leakage in brake valve. Leakage in brake piston seal. Do brake accumulator check.
Do brake pump standby pressure test. Do brake valve pressure test. Bleed brakes. Inspect brake surface material. Do brake valve leakage test. Check for an over filled differential. Apply brakes and check for leakage from check plug. öIt is normal for the oil level to be slightly above the check plug. Aggressive brakes Internal restriction in circuit. Brake valve malfunction. Low oil level. Remove lines and components. Disassemble and inspect. Check oil level. Brakes drag Brake pedal not returning properly. Debris holding valve partially open in brake valve. Warped brake disk. Stuck brake piston. Inspect floor mat and pedal. Do brake valve pressure test. Inspect brake disk. Repair.
Brakes lock up Brake valve malfunction. Clean or replace brake valve.