Precautions in Diagnosing Troubles
To ensure that the trouble diagnosis is done accurately and smoothly, observe the following and follow ABS CHECK .
- If the vehicles was operated in any of the following ways, ABS warning lamp may light momentarily but this does not indicate anything abnormal in ABS.
- The vehicle was driven with parking brake pulled.
- The vehicle was driven with brake dragging.
- The vehicle was stuck in mud, sand, etc.
- Wheel spin occurred while driving.
- Wheel(s) was rotated while the vehicle was jacked up.
- Be sure to read Precautions for Electrical Circuit Service before inspection and observe what is written there.
- Be sure to use the trouble diagnosis procedure as described in ABS CHECK . Failure to follow it may result in incorrect diagnosis. (Some other diagnosis trouble code may be stored by mistake in the memory of ABS control module during inspection.)
- When disconnecting ABS hydraulic unit / control module connector (1), pull down lock lever (2) of connector.
When connecting, set the connector on ABS hydraulic unit / control module assembly and pull up the lock lever (2) until it locks.
- Inspect the vehicle for any mechanical conditions related the brake system.
- Brake reservoir fluid level correct.
- Inspect master for fluid for contamination.
- Inspect brake master / modulator for leaks.
- Inspect brake components at all wheels.
- Verify no brake drag exists (brake switch adjustment).
- Verify even brake apply (no pull or lead).
- Inspect for worn / damaged brake pads.
- Inspect for worn / damaged wheel bearings.
- Inspect wheel speed sensors / wiring.
- Inspect harness connectors / wheel speed sensor rotors for damage.
- Inspect tires for tread depth / wear.
- Road test the vehicle to verify the complaint.
- Current DTC memorized in ABS control module can not be cleared, but history DTC can be cleared.
- Current DTC is memorized as history DTC to ABS control module when ABS control module diagnoses conditions of the system as normal.