Diagnostic Routine AJ
Diagnostic Routine AJ
Diagnostic Overview
Wheel Speed Sensor Electrical Fault DTCs - Front
Refer to Wiring Diagram Set 42 for schematic and connector information Electrical Diagrams.
Normal Operation and Fault Conditions
REFER to Wheel Speed Sensor .
When the ignition is set to ON, the ABS (Anti-Lock Brake System) module carries out a self-test by sending a reference voltage through the wheel speed sensors and their circuitry.
DTC Fault Trigger Conditions
Visual Inspection and Diagnostic Pre-checks
- Make sure the wheel speed sensor harness is routed correctly and is undamaged.
- Make sure the wheel speed sensor electrical connector is free from any corrosion or other contaminants.
Special Tool(s)
Pinpoint Test
1. CHECK FOR FAULT REPEATABILITY
1. Ignition ON.
2. Using a scan tool, clear all ABS (Anti-Lock Brake System) module DTCs (Diagnostic Trouble Codes).
3. Test drive the vehicle above 20 km/h (12.4 mph) and carry out at least 1 ABS (Anti-Lock Brake System) stop.
4. Bring the vehicle to a safe stop.
5. Ignition OFF.
6. Ignition ON.
7. Using a scan tool, carry out the ABS (Anti-Lock Brake System) module self-test.
Is the DTC (Diagnostic Trouble Code) still present?
2. CHECK THE ABS (Anti-Lock Brake System) MODULE OUTPUT USING THE ROTUNDA ABS (Anti-Lock Brake System) ACTIVE WHEEL SPEED SENSOR TESTER
1. Ignition OFF.
2. Disconnect suspect wheel speed sensor electrical connector.
3. Connect the Rotunda ABS (Anti-Lock Brake System) Active Wheel Speed Sensor Tester to the wheel speed sensor connectors.
4. Ignition ON.
5. Select the correct system polarity on the Rotunda ABS (Anti-Lock Brake System) Active Wheel Speed Sensor Tester and turn the power switch to the ON position.
Is the tester output LED (Light-emitting Diode) illuminated?
3. CHECK THE WHEEL SPEED SENSOR OUTPUT WITH THE ROTUNDA ABS (Anti-Lock Brake System) ACTIVE WHEEL SPEED SENSOR TESTER
1. Raise the suspect wheel until it can spin freely. REFER to Lifting Points .
2. While monitoring the Rotunda ABS (Anti-Lock Brake System) Active Wheel Speed Sensor Tester, slowly spin the suspect wheel.
Do the sensor output LEDs (Light-emitting Diodes) illuminate and flash and is the current overload LED (Light-emitting Diode)not illuminated?
4. CHECK THE WHEEL SPEED SENSOR CIRCUITS FOR A SHORT TO BATTERY VOLTAGE
1. Ignition OFF.
2. Disconnect ABS (Anti-Lock Brake System) Module electrical connector.
3. Disconnect suspect wheel speed sensor electrical connector.
4. Ignition ON.
5. For the LF (Left Front) wheel speed sensor, measure:
6. For the RF (Right Front) wheel speed sensor, measure:
Is any voltage present?
5. CHECK THE WHEEL SPEED SENSOR CIRCUITS FOR AN OPEN
1. Ignition OFF.
2. For the LF (Left Front) wheel speed sensor, measure:
3. For the RF (Right Front) wheel speed sensor, measure:
Are the resistances less than 3 ohms?
6. CHECK FOR SHORTED WHEEL SPEED SENSOR CIRCUITS
1. For the LF (Left Front) wheel speed sensor, measure:
2. For the RF (Right Front) wheel speed sensor, measure:
Is the resistance greater 10,000 ohms?
7. CHECK THE WHEEL SPEED SENSOR CIRCUITS FOR A SHORT TO GROUND
1. For the LF (Left Front) wheel speed sensor, measure:
2. For the RF (Right Front) wheel speed sensor, measure:
Are the resistances greater than 10,000 ohms?
8. CHECK FOR CORRECT ABS (Anti-Lock Brake System) MODULE OPERATION
1. Inspect the ABS (Anti-Lock Brake System) module electrical connector.
2. Repair:
- corrosion (install new connector or terminal - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary
3. Connect the ABS (Anti-Lock Brake System) module electrical connector. Make sure it seats and latches correctly.
4. Connect any disconnected wheel speed sensor electrical connectors. Make sure the electrical connector seats and latches correctly.
5. Operate the system and determine if the concern is still present.
Is the concern still present?
