C1230 (REAR)
Anti-Lock Control - Three-Channel
Pinpoint Test D: DTCs C1145 (RF), C1155 (LF) or C1230 (REAR)
Normal Operation
The active wheel speed sensors generate a square wave signal that is sent to the ABS module. The wheel speed sensor circuitry connects to the ABS module through 2 wires and a connector at each wheel speed sensor. When the ignition is turned to the RUN position, the ABS module carries out a self-test by sending a reference voltage to all of the wheel speed sensors and their circuitry to determine if they are functional.
Voltage and ground signals are supplied to the wheel speed sensors from the ABS module.
- DTC C1145 (Wheel Speed Sensor RF Input Circuit Failure)- a continuous and on-demand DTC that sets when the vehicle speed exceeds 5 km/h (3 mph), if the ABS module detects an open, short to ground or voltage or a defective RF wheel speed sensor trigger circuit.
- DTC C1155 (Wheel Speed Sensor LF Input Circuit Failure)- a continuous and on-demand DTC that sets when the vehicle speed exceeds 5 km/h (3 mph), if the ABS module detects an open, short to ground or voltage or a defective LF wheel speed sensor trigger circuit.
- DTC C1230 (Speed Wheel Sensor Rear Center Input Circuit Failure)- a continuous and on-demand DTC that sets when the vehicle speed exceeds 5 km/h (3 mph), if the ABS module detects an open, short to ground or voltage or a defective rear wheel speed sensor trigger circuit.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Wheel speed sensor
- ABS module
PINPOINT TEST D : DTCs C1145 (RF), C1155 (LF) OR C1230 (REAR)
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
D1 CHECK FOR FAULT REPEATABILITY
NOTE: Both circuits must be checked for each DTC.
- Connect the scan tool.
- Ignition ON.
- Using a scan tool, clear the Continuous Memory Diagnostic Trouble Codes (CMDTCs)
- Drive the vehicle at least 16 km/h (10 mph).
- Enter the following diagnostic mode on the scan tool: Self Test- ABS Module.
Is DTC C1145, C1155 or C1230 retrieved?
Yes
If the Rotunda Active Wheel Speed Sensor Tester is not available, GO to D4.
If the Rotunda Active Wheel Speed Sensor Tester is available, GO to D2.
No
INSPECT the wheel speed sensors, wheel speed sensor wiring and wheel speed sensor tone rings. REPAIR or INSTALL new as necessary. If any other DTCs are retrieved, REFER to the ABS Module DTC Chart - Three-Channel. Anti-Lock Control - Three-Channel
D2 CHECK THE ABS MODULE OUTPUT USING THE ROTUNDA ACTIVE WHEEL SPEED SENSOR TESTER
- Ignition OFF.
- Disconnect: Suspect Wheel Speed Sensor.
- Connect the Rotunda Active Wheel Speed Sensor Tester to the wheel speed sensor connectors.
- Ignition ON.
- Select the correct system polarity on the tester and turn the tester power switch to the ON position.
Is the module output LED illuminated?
Yes
GO to D3.
No
GO to D6.
D3 CHECK THE WHEEL SPEED SENSOR OUTPUT WITH THE ROTUNDA ACTIVE WHEEL SPEED SENSOR TESTER
- Raise the suspect wheel until it can spin freely.
- While monitoring the Rotunda Active Wheel Speed Sensor Tester, slowly spin the suspect wheel.
Do the tester output LEDs illuminate and flash and is the current overload LED not illuminated?
Yes
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.
No
If the current level LED is not illuminated and the sensor output LEDs do not illuminate or if the current level LED is illuminated red, INSTALL a new wheel speed sensor. REFER to Wheel Speed Sensor - Front, Rear Wheel Drive (RWD) , Wheel Speed Sensor - Front, Four Wheel Drive (4WD) or Wheel Speed Sensor - Rear, Three-Channel . CLEAR the DTCs. REPEAT the self-test.
D4 CHECK THE WHEEL SPEED SENSOR CIRCUITS FOR A SHORT TO VOLTAGE
NOTE: Both circuits must be checked for each DTC.
- Ignition OFF.
- Disconnect: ABS Module C135.
- Disconnect: Suspect Wheel Speed Sensor.
- Ignition ON.
- Measure the voltage between the ABS module C135, harness side and ground as follows:
DTC ABS Module Connector-Pin Circuit C1145 C135-3 VCA05 (GY/VT) C135-4 RCA19 (VT) C1155 C135-27 VCA03 (VT/WH) C135-28 RCA17 (YE) C1230 C135-35 RCA21 (BN/GN) C135-36 VCA07 (BU/OG)
Is any voltage present?
Yes
REPAIR the affected circuit(s) for a short to voltage. CLEAR the DTCs. REPEAT the self-test.
No
GO to D5.
D5 CHECK THE WHEEL SPEED SENSOR CIRCUITS FOR A SHORT TO GROUND
- Ignition OFF.
- Measure the resistance between the ABS module C135, harness side and ground as follows:
DTC ABS Module Connector-Pin Circuit C1145 C135-3 VCA05 (GY/VT) C135-4 RCA19 (VT) C1155 C135-27 VCA03 (VT/WH) C135-28 RCA17 (YE) C1230 C135-35 RCA21 (BN/GN) C135-36 VCA07 (BU/OG)
Are the resistances greater than 10,000 ohms?
Yes
GO to D6.
No
REPAIR the affected circuit(s). CLEAR the DTCs. REPEAT the self-test.
D6 CHECK THE WHEEL SPEED SENSOR CIRCUITS FOR AN OPEN
- Measure the resistance between the ABS module C135, harness side and the suspect wheel speed sensor connector, harness side as follows:
DTC ABS Module Circuit Wheel Speed Sensor C1145 C135-3 VCA05 (GY/VT) C160-1 C135-4 RCA19 (VT) C160-2 C1155 C135-27 VCA03 (VT/WH) C150-1 C135-28 RCA17 (YE) C150-2 C1230 C135-35 RCA21 (BN/GN) C455-2 C135-36 VCA07 (BU/OG) C455-1
Are the resistances less than 5 ohms?
Yes
GO to D7.
No
REPAIR the open in the affected circuit(s). CLEAR the DTCs. REPEAT the self-test.
D7 CHECK WHEEL SPEED SENSOR CIRCUITS FOR A SHORT TOGETHER
- Measure the resistance between the suspect wheel speed sensor connector, harness side as follows:
DTC Wheel Speed Sensor Circuit Wheel Speed Sensor C1145 C160-1 VCA05 (GY/VT) / RCA19 (VT) C160-2 C1155 C150-1 VCA03 (VT/WH) / RCA17 (YE) C150-2 C1230 C455-1 VCA07 (BU/OG) / RCA21 (BN/GN) C455-2
Is the resistance greater than 10,000 ohms?
Yes
GO to D8.
No
REPAIR the affected circuit(s) for a short together. CLEAR the DTCs. REPEAT the self-test.
D8 CHECK THE ABS MODULE OUTPUT
- Connect: ABS Module C135.
- Ignition ON.
- Measure the voltage between the suspect front wheel speed sensor pins, harness side.
- Measure the voltage between the suspect rear wheel speed sensor pins, harness side.
Are the voltages greater than 10 volts?
Yes
INSTALL a new wheel speed sensor. REFER to Wheel Speed Sensor - Front, Rear Wheel Drive (RWD) , Wheel Speed Sensor - Front, Four Wheel Drive (4WD) or Wheel Speed Sensor - Rear, Three-Channel . CLEAR the DTCs. REPEAT the self-test.
No
GO to D9.
D9 CHECK THE ABS MODULE CONNECTORS
- Disconnect the ABS module connector.
- Check for:
- corrosion.
- pushed-out pins.
- spread terminals.
- Connect the ABS module connector and make sure that it is seated correctly.
- Operate the system and verify the concern is still present.
Is the concern still present?
Yes
INSTALL a new ABS module. REFER to Anti-Lock Brake System (ABS) Module . TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. TEST the system for normal operation.