Antilock Brake System (ABS): 1100
1100-LEFT FRONT WHEEL SPEED SENSOR CIRCUIT
When Monitored and Set Condition
^ When Monitored (Supply circuit): Ignition on. The Controller Antilock Brake (CAB) monitors the wheel speed circuit every 7 milliseconds (ms).
^ When Monitored (Signal circuit): Wheel speed comparison is checked at drive off or every 7 milliseconds (ms). Sensor Signal continuity is checked every 7 milliseconds. Wheel speed phase length supervision is checked every 7 milliseconds.
^ Set Condition (Supply circuit): If the CAB detects an open or shorted wheel speed sensor circuit, the Diagnostic Trouble Code (DTC) will set.
^ Set Condition (Signal circuit): If, during an ABS stop, the CAB commands any valve solenoid on for an extended length of time, and does not see a corresponding wheel speed change, the Diagnostic Trouble Code (DTC) is set. The DTC can also set if the Signal is missing or erratic.
POSSIBLE CAUSES
- LEFT FRONT WHEEL SPEED SENSOR 12 VOLT SUPPLY CIRCUIT SHORT TO VOLTAGE
- LEFT FRONT WHEEL SPEED SENSOR 12 VOLT SUPPLY CIRCUIT SHORT TO GROUND
- LEFT FRONT WHEEL SPEED SENSOR 12 VOLT SUPPLY CIRCUIT OPEN
- LEFT FRONT WHEEL SPEED SENSOR SIGNAL CIRCUIT SHORT TO GROUND
- LEFT FRONT WHEEL SPEED SENSOR SIGNAL CIRCUIT SHORT TO VOLTAGE
- LEFT FRONT WHEEL SPEED SENSOR SIGNAL CIRCUIT OPEN
- LEFT FRONT WHEEL SPEED SENSOR CIRCUITS SHORT TOGETHER
- SENSOR OR TONE WHEEL DAMAGE
- WHEEL SPEED SENSOR
- CONTROLLER ANTILOCK BRAKE (CAB)
For a complete Antilock Brake System (ABS) Circuit Diagram, (Refer to -BRAKES/ELECTRICAL - SCHEMATICS AND DIAGRAMS).
Diagnostic Test
1. WITH THE DRBIII READ DTCs
Turn the ignition on. With the DRBIII, record and erase DTCs. Turn the ignition off. Turn the ignition on. With the DRBIII, read DTCs.
Does the DRBIII display a Left Front Wheel Speed Sensor Circuit DTC?
Yes >> Go to 2
No >> Go to 13
2. INSPECT THE LEFT FRONT WHEEL SPEED SENSOR
Turn the ignition off. Inspect the Left Front Wheel Speed Sensor and connector.
Is the Sensor or Connector damaged?
Yes >> Repair as necessary. Perform ABS VERIFICATION TEST. ABS Verification Test
No >> Go to 3
3. MEASURE THE VOLTAGE OF THE LEFT FRONT WHEEL SPEED SENSOR 12 VOLT SUPPLY CIRCUIT
With the ignition off. Disconnect the Left Front Wheel Speed Sensor harness connector.
Note: Check connectors - Clean/repair as necessary.
Turn the ignition on.
Measure the voltage of the Left Front Wheel Speed Sensor 12 Volt Supply circuit at the Left Front Wheel Speed Sensor harness connector.
Is the voltage above 10 volts?
Yes >> Go to 8
No >> Go to 4
4. MEASURE THE VOLTAGE OF THE LEFT FRONT WHEEL SPEED SENSOR 12 VOLT SUPPLY CIRCUIT
Turn the ignition off. Measure the voltage of the Left Front Wheel Speed Sensor 12 Volt Supply circuit at the Left Front Wheel Speed Sensor harness connector.
Is the voltage below 1.0 volt?
Yes >> Go to 6
No >> Go to 5
5. CHECK THE LEFT FRONT WHEEL SPEED SENSOR 12 VOLT SUPPLY CIRCUIT FOR A SHORT TO VOLTAGE
With the ignition off. Disconnect the CAB harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the voltage of the Left Front Wheel Speed Sensor 12 Volt Supply circuit.
Is the voltage below 1.0 volt?
Yes >> Replace the Controller Antilock Brake (CAB) Module. Perform ABS VERIFICATION TEST. ABS Verification Test
No >> Repair the Left Front Wheel Speed Sensor 12 Volt Supply circuit for a short to voltage. Perform ABS VERIFICATION TEST. ABS Verification Test
6. MEASURE THE RESISTANCE BETWEEN GROUND AND THE LEFT FRONT WHEEL SPEED SENSOR 12 VOLT SUPPLY CIRCUIT
With the ignition off. Disconnect the CAB harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance between ground and the Left Front Wheel Speed Sensor 12 Volt Supply circuit at the CAB harness connector.
Is the resistance below 100k ohms?
Yes >> Repair the Left Front Wheel Speed Sensor 12 Volt Supply circuit for a short to ground. Perform ABS VERIFICATION TEST. ABS Verification Test
No >> Go to 7
7. MEASURE THE RESISTANCE OF THE LEFT FRONT WHEEL SPEED SENSOR 12 VOLT SUPPLY CIRCUIT
With the ignition off.
Measure the resistance of the Left Front Wheel Speed Sensor 12 Volt Supply circuit from the CAB harness connector to the Left Front Wheel Speed Sensor harness connector.
Is the resistance below 5.0 ohms?
Yes >> Go to 8
No >> Repair the Left Front Wheel Speed Sensor 12 Volt Supply circuit for an open. Perform ABS VERIFICATION TEST. ABS Verification Test
8. MEASURE THE RESISTANCE OF THE LEFT FRONT WHEEL SPEED SENSOR SIGNAL CIRCUIT
With the ignition off. Reconnect the CAB harness connector. Measure the resistance between ground and the Left Front Wheel Speed Sensor Signal circuit.
Is the resistance less than 100 ohms?
Yes >> Go to 11
No >> Go to 9
9. MEASURE THE RESISTANCE OF THE LEFT FRONT WHEEL SPEED SENSOR SIGNAL CIRCUIT
With the ignition off.
Measure the resistance between ground and the Left Front Wheel Speed Sensor Signal circuit.
Is the resistance greater than 300 ohms?
Yes >> Go to 10
No >> Replace the Left Front Wheel Speed Sensor.
10. MEASURE THE RESISTANCE OF THE LEFT FRONT WHEEL SPEED SENSOR SIGNAL CIRCUIT
With the ignition off. Disconnect the CAB harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance of the Left Front Wheel Speed Sensor Signal circuit from the CAB harness connector to the Left Front Wheel Speed Sensor harness connector.
Is the resistance below 5.0 ohms?
Yes >> Go to 12
No >> Repair the Left Front Wheel Speed Sensor Signal circuit for an open. Perform ABS VERIFICATION TEST. ABS Verification Test
11. MEASURE THE RESISTANCE BETWEEN GROUND AND THE LEFT FRONT WHEEL SPEED SENSOR SIGNAL CIRCUIT
With the ignition off. Disconnect the CAB harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance between ground and the Left Front Wheel Speed Sensor Signal circuit at the CAB harness connector.
Is the resistance below 100k ohms?
Yes >> Repair the Left Front Wheel Speed Sensor Signal circuit for a short to ground. Perform ABS VERIFICATION TEST. ABS Verification Test
No >> Go to 12
12. MEASURE THE RESISTANCE BETWEEN THE LEFT FRONT WHEEL SPEED SENSOR 12 VOLT SUPPLY CIRCUIT AND THE SENSOR SIGNAL CIRCUIT
With the ignition off.
Measure the resistance between the Left Front Wheel Speed Sensor 12 Volt Supply circuit and the Left Front Wheel Speed Sensor Signal circuit at the CAB harness connector.
Is the resistance below 100k ohms?
Yes >> Repair the Left Front Wheel Speed Sensor 12 Volt Supply circuit for a short to the Left Front Wheel Speed Sensor Signal circuit. Perform ABS VERIFICATION TEST. ABS Verification Test
No >> Replace the Controller Antilock Brake (CAB) Module. Perform ABS VERIFICATION TEST. ABS Verification Test
13. VISUALLY INSPECT COMPONENTS FOR DAMAGE AND CORRECT INSTALLATION
Visually inspect the related wiring harness and connectors. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out, or corroded terminals. Visually inspect the Left Front Wheel Speed Sensor, connector and tone wheel for damage and correct installation.
Are there any visible Sensor, connector or tone wheel concerns?
Yes >> Correct the sensor, connector or tone wheel concerns as necessary. Perform ABS VERIFICATION TEST. ABS Verification Test
No >> Go to 14
14. MONITOR ALL WHEEL SPEED SENSORS WITH THE DRBIII
With the DRBIII, erase DTCs.
Start the engine.
With an assistant to drive, use the DRBIII to monitor all wheel speed sensors. Slowly accelerate as straight as possible from a stop to 24 km/h (15 MPH).
Is the Left Front Wheel Speed Sensor Signal 0 or differing from others by more than 5 km/h (3 MPH)?
Yes >> Replace the Left Front Wheel Speed Sensor.
No >> Inspect and repair the related wiring harness for a possible intermittent condition. Perform ABS VERIFICATION TEST. ABS Verification Test