POSSIBLE CAUSE
A. OIL LEVEL IS LOW.
B. DRIVE AXLE OIL IS CONTAMINATED.
C. PARKING BRAKE IS NOT RELEASED.
D. PARKING BRAKE HAND LEVER IS OUT OF ADJUSTMENT.
E. SERVICE BRAKE SYSTEM DAMAGED/MALFUNCTION.
F. OIL COOLER CIRCUIT RESTRICTED.
G. EXCESSIVE WEAR ON INTERNAL WET DISC SERVICE BRAKES.
CAUSE A – OIL LEVEL IS LOW
PROCEDURE OR ACTION:
- Check drive axle oil level.
Is drive axle oil level low?
YES: Fill drive axle to proper level. See Operating Manual.
NO: Go to Step 2. - Check transmission oil level.
Is transmission oil level low?
YES: Fill transmission to proper level. See Operating Manual.
NO: Go to CAUSE B.
CAUSE B – DRIVE AXLE OIL IS CONTAMINATED
PROCEDURE OR ACTION:
- Take Oil Sample for analysis before changing oil. Refer to appropriate Drive Axle Repair or Drive Axle and Differential Assembly Repair manual, depending on lift truck model.
Is drive axle oil contaminated?
YES: Replace transmission and drive axle oil. See Operating Manual.
NO: Go to CAUSE C.
CAUSE C – PARKING BRAKE IS NOT RELEASED
PROCEDURE OR ACTION:
- Release parking brake.
- Inspect parking brake lever mechanism for interference.
Does parking brake lever mechanism have interference?
YES: Loosen parking brake lever and remove interference of lever mechanism. Refer to appropriate Brake System manual, depending on lift truck model.
NO: Go to CAUSE D. - Verify correct operation of park brake cable return spring.
CAUSE D – PARKING BRAKE HAND LEVER IS OUT OF ADJUSTMENT
PROCEDURE OR ACTION:
- Check parking brake hand lever tension.
Is parking brake hand lever tension too tight?
YES: Loosen parking brake hand lever tension. Refer to appropriate Brake System manual, depending on lift truck model.
NO: Go to Step 2. - Check correct operation of connecting cables and linkage.
Are connecting cables and linkages operating correctly?
YES: Go to CAUSE E.
NO: Correct connecting cables or linkage for parking brake. Refer to appropriate Brake System manual, depending on lift truck model.
CAUSE E – SERVICE BRAKE SYSTEM DAMAGED/MALFUNCTION
PROCEDURE OR ACTION:
- Inspect brake system for leaks, binding, or damage.
Is brake system leaking, binding, or damaged?
YES: Repair or replace brakes. Refer to appropriate Brake System manual, depending on lift truck model.
Inspect for cause of leakage, binding, or damage and correct as necessary.
NO: Perform brake system operational check. See Operational Checkout Procedures.
CAUSE F – OIL COOLER CIRCUIT RESTRICTED
PROCEDURE OR ACTION:
- Check oil cooler and lines for a restriction. Perform Transmission Pressure Test.
Is converter pressure out of specification?
YES: Back flush the oil cooler and lines to remove internal debris. Replace oil cooler and lines as necessary.
Refer to appropriate Powershift Transmission, Repair or Three-Speed Powershift Transmission Repair
manual, depending on lift truck model.
NO: Go to CAUSE G.
CAUSE G – EXCESSIVE WEAR ON INTERNAL WET DISC SERVICE BRAKES
PROCEDURE OR ACTION:
- Raise front drive axle so both wheels are off ground. Secure lift truck. Refer to appropriate Periodic
Maintenance manual, depending on lift truck model. Check drive axle drag by turning one wheel by hand.
Perform Operational Diagnostic Procedures, Operational Checkout, Page 9010-05-10.
Does opposite wheel have excessive drag?
YES: Inspect and repair drive axle. Refer to appropriate Drive Axle Repair or Drive Axle and Differential
Assembly Repair manual, depending on lift truck model.
NO: Perform brake system operational check.