ABS (DIAGNOSTICS) > General Diagnostic Table

INSPECTION

Symptoms

Problem parts

Vehicle instability during braking

Vehicle is pulled to either right or left side.

• ABSCM&H/U (solenoid valve)

• ABS wheel speed sensor

• Brake (caliper, piston and pad)

• Wheel alignment

• Tire specifications, tire wear and air pressures

• Incorrect wiring or piping connections

• Road surface (uneven, camber)

Vehicle spin

• ABSCM&H/U (solenoid valve)

• ABS wheel speed sensor

• Brake (pad)

• Tire specifications, tire wear and air pressures

• Incorrect wiring or piping connections

Poor brake performance

Long braking/stopping distance

• ABSCM&H/U (solenoid valve)

• Brake (pad)

• Air in brake line

• Tire specifications, tire wear and air pressures

• Incorrect wiring or piping connections

Wheel lock

• ABSCM&H/U (solenoid valve, motor)

• ABS wheel speed sensor

• Incorrect wiring or piping connections

Brake drag

• ABSCM&H/U (solenoid valve)

• ABS wheel speed sensor

• Master cylinder

• Brake (caliper and piston)

• Parking brake

• Axle and wheels

• Brake pedal play

Long brake pedal stroke

• Air in brake line

• Brake pedal play

Vehicle vertical pitching

• Suspension play or fatigue (reduced damping)

• Incorrect wiring or piping connections

• Road surface (uneven)

Unstable or uneven braking

• ABSCM&H/U (solenoid valve)

• ABS wheel speed sensor

• Brake (caliper, piston and pad)

• Tire specifications, tire wear and air pressures

• Incorrect wiring or piping connections

• Road surface (uneven)

Vibration and/or noise

(while driving on slippery roads)

Excessive pedal vibration

• Incorrect wiring or piping connections

• Road surface (uneven)

Noise from the ABSCM&H/U

• ABSCM&H/U (mount bushing)

• ABS wheel speed sensor

• Brake line

Noise from front of vehicle

• ABSCM&H/U (mount bushing)

• ABS wheel speed sensor

• Master cylinder

• Brake (caliper, piston, pad and rotor)

• Brake line

• Brake booster and check valve

• Suspension play or fatigue (reduced damping)

Noise from rear of vehicle

• ABS wheel speed sensor

• Brake (caliper, piston, pad and rotor)

• Parking brake

• Brake line

• Suspension play or fatigue (reduced damping)