Diagnostic Instructions

DTC Descriptor

DTC C0035 00: Left Front Wheel Speed Sensor Circuit

DTC C0040 00: Right Front Wheel Speed Sensor Circuit

DTC C0045 00: Left Rear Wheel Speed Sensor Circuit

DTC C0050 00:  Right Rear Wheel Speed Sensor Circuit

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Left Front Sensor Voltage	C0035 00	C0035 00	--	C0035 00
Left Front Sensor Signal	C0035 00	C0035 00	C0035 00	C0035 00
Right Front Sensor Voltage	C0040 00	C0040 00	--	C0040 00
Right Front Sensor Signal	C0040 00	C0040 00	C0040 00	C0040 00
Left Rear Sensor Voltage	C0045 00	C0045 00	--	C0045 00
Left Rear Sensor Signal	C0045 00	C0045 00	C0045 00	C0045 00
Right Rear Sensor Voltage	C0050 00	C0050 00	--	C0050 00
Right Rear Sensor Low Reference	C0050 00	C0050 00	C0050 00	C0050 00

Component	Condition	DTCs
Left Front Wheel Speed Sensor	•  Physical damage     •  Debris on the wheel speed sensor or the encoder ring     •  Loose or improperly mounted sensor     •  Loose or worn wheel bearing     •  Air gap between the wheel speed sensor and the encoder ring too large	C0035 00
Right Front Wheel Speed Sensor	•  Physical damage     •  Debris on the wheel speed sensor or the encoder ring     •  Loose or improperly mounted sensor     •  Loose or worn wheel bearing     •  Air gap between the wheel speed sensor and the encoder ring too large	C0040 00
Left Rear Wheel Speed Sensor	•  Physical damage     •  Debris on the wheel speed sensor or the encoder ring     •  Loose or improperly mounted sensor     •  Loose or worn wheel bearing     •  Air gap between the wheel speed sensor and the encoder ring too large	C0045 00
Right Rear Wheel Speed Sensor	•  Physical damage     •  Debris on the wheel speed sensor or the encoder ring     •  Loose or improperly mounted sensor     •  Loose or worn wheel bearing     •  Air gap between the wheel speed sensor and the encoder ring too large	C0050 00

Circuit/System Description

The wheel speed sensor receives ignition voltage from the electronic brake control module (EBCM) and provides an output signal to the EBCM. As the wheel spins, the wheel speed sensor sends a DC square wave signal. The EBCM uses the frequency of the square wave signal to calculate the wheel speed.

Conditions for Running the DTC

C0035-C0050 00

Conditions for Setting the DTC

C0035-C0050 00

A short to voltage, short to ground or an open/high resistance is detected on a wheel speed sensor circuit.

Action Taken When the DTC Sets

Conditions for Clearing the DTC

Diagnostic Aids

If 2 or more wheel speed sensors are inoperative diagnose each wheel speed sensor individually.

If the customer comments that the ABS indicator is ON only during moist environmental conditions: rain, snow, vehicle wash, etc., inspect the wheel speed sensor wiring for signs of water intrusion. If the DTC is not current, clear all DTCs and simulate the effects of water intrusion by using the following procedure:

1. Spray the suspected area with a 5 percent saltwater solution. To create a 5 percent saltwater solution, add 2 teaspoons of salt to 8 fl oz of water (10 g of salt to 200 ml of water).
2. Test drive the vehicle over various road surfaces, bumps, turns, etc., above 40 km/h (25 mph) for at least 30 seconds. Also rotate steering wheel from stop to stop for intermittent condition caused from open or chaffing of the front wheel speed sensor harness.
3. If the DTC returns, replace the suspected wheel speed sensor or repair the wheel speed sensor wiring.
4. Rinse the area thoroughly when completed.

Reference Information

Schematic Reference

Antilock Brake System Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

ABS Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Ignition ON, observe the scan tool Wheel Speed Sensor parameter. The reading should be the same speed on all sensors when driving in a straight line at a speed greater than 20 km/h (13 mph).

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the EBCM.
2. Ignition ON, test for less than 1 volt between the 12 volt reference circuit terminal of the appropriate sensor listed below and ground.

•	LF Sensor circuit terminal 45

•	RF Sensor circuit terminal 34

•	LR Sensor circuit terminal 36

•	RR Sensor circuit terminal 43

⇒	If greater than the specified range, test the12 volt reference circuit for a short to voltage.

3. Test for less than 1 volt between the signal circuit terminal of the appropriate sensor listed below and ground.

•	LF Sensor circuit terminal 46

•	RF Sensor circuit terminal 33

•	LR Sensor circuit terminal 37

•	RR Sensor circuit terminal 42

⇒	If greater than the specified range, test the signal circuit for a short to voltage.

4. Ignition OFF, test for infinite resistance between the 12 volt reference terminal of the appropriate sensor listed below and ground.

•	LF Sensor circuit terminal 45

•	RF Sensor circuit terminal 34

•	LR Sensor circuit terminal 36

•	RR Sensor circuit terminal 43

⇒	If less than the specified value, test the 12 volt reference circuit for a short to ground.

5. Ignition OFF, test for infinite resistance between the following signal circuit terminal of the appropriate sensor listed below and ground.

•	LF Sensor circuit terminal 46

•	RF Sensor circuit terminal 33

•	LR Sensor circuit terminal 37

•	RR Sensor circuit terminal 42

⇒	If less than the specified value, test the signal circuit for a short to ground.

6. Ignition OFF, disconnect the harness connector at the appropriate WSS.
7. Ignition OFF, test for less than 2 ohms between the appropriate12 volt reference circuit terminals listed below.

•	LF Sensor circuit terminal 45 at the EBCM harness connector and terminal B at the WSS harness connector.

•	RF Sensor circuit terminal 34 at the EBCM harness connector and terminal B at the WSS harness connector.

•	LR Sensor circuit terminal 36 at the EBCM harness connector and terminal B at the WSS harness connector.

•	RR Sensor circuit terminal 43 at the EBCM harness connector and terminal B at the WSS harness connector.

⇒	If greater than the specified value, test the 12 volt reference circuit for an open or high resistance.

8. Test for less than 2 ohms between the appropriate signal circuit terminals listed below.

•	LF Sensor circuit terminal 46 at the EBCM harness connector and terminal A at the WSS harness connector.

•	RF Sensor circuit terminal 33 at the EBCM harness connector and terminal A at the WSS harness connector.

•	LR Sensor circuit terminal 37 at the EBCM harness connector and terminal A at the WSS harness connector.

•	RR Sensor circuit terminal 42 at the EBCM harness connector and terminal A at the WSS harness connector.

⇒	If greater than the specified value, test the signal circuit for an open or high resistance.

9. If all circuits test normal, replace the appropriate wheel speed sensor. If the DTC resets replace the EBCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.