Antilock Brakes / Traction Control Systems: Testing and Inspection

ABS FAULT DIAGNOSIS
If a fault has occurred, or has been identified by electronic control unit (ECU) self diagnostic function and ABS warning light is illuminated, the system and components must be checked to locate and rectify fault, using Testbook (a Land Rover diagnostic special tool) diagnostics.





NOTE: DTC's can only be Extracted, Diagnosed and Cleared by the TestBook Diagnostic Unit, a required special tool, or an appropriate after market equivalent.

All information regarding DTC's for this model is contained within the Land Rover TestBook Diagnostic Unit. The manufacture does not provide any other information on How to Pull Codes, Trouble Code Descriptions, Diagnosis and Testing of Trouble Codes or How to Clear codes.

NOTE: If warning lamp has indicated a fault in system, and no fault code has been stored in memory, cause of fault could be:
^ Failure in electrical supply
^ Loss of hydraulic pressure
^ Faulty pressure switch
^ Bad ECU ground
^ Faulty warning light relay
^ System not fully charged before driving away
^ ECU not connected

Before commencing fault diagnosis procedure following items must be checked:
1. Inspect all exposed cables for damage or abrasion.
2. Check ground on ABS system.
3. Battery - state of charge.
4. Fluid level in reservoir.
5. All ABS fuses and electrical connections.
6. Check hub end-float.


Fault rectification
1. Complete harness should be replaced if faults are found in wiring harness.
2. DO NOT use unspecified cables or connectors, as this could jeopardize safe function of ABS.
3. DO NOT attempt to open sealed 35 way connector to ECU.

NOTE:
- If ABS warning light illuminates due to large sensor air gap, fault will be retained by the ECU memory. Where wheel sensors have been pushed fully home prior to test, the ECU will indicate a fault that has been rectified.
- After any steering adjustment, bearing replacement/adjustment, brake disc replacement: Check hub end/float and sensor clearance.