Diagnostic Instructions

DTC Descriptors

DTC C0035 00: Left Front Wheel Speed Sensor Circuit No Additional Information

DTC C0035 0F: Left Front Wheel Speed Sensor Circuit Erratic Signal

DTC C0035 18: Left Front Wheel Speed Sensor Circuit Signal Amplitude Less Than Minimum

DTC C0040 00: Right Front Wheel Speed Sensor Circuit No Additional Information

DTC C0040 0F: Right Front Wheel Speed Sensor Circuit Erratic Signal

DTC C0040 18: Right Front Wheel Speed Sensor Circuit Signal Amplitude Less Than Minimum

DTC C0045 00: Left Rear Wheel Speed Sensor Circuit No Additional Information

DTC C0045 0F: Left Rear Wheel Speed Sensor Circuit Erratic Signal

DTC C0045 18: Left Rear Wheel Speed Sensor Circuit Signal Amplitude Less Than Minimum

DTC C0050 00: Right Rear Wheel Speed Sensor Circuit No Additional Information

DTC C0050 0F: Right Rear Wheel Speed Sensor Circuit Erratic Signal

DTC C0050 18: Right Rear Wheel Speed Sensor Circuit Signal Amplitude Less Than Minimum

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Left Front Sensor Signal	C0035 00	C0035 00	C0035 00	C0035 0F, 18
Left Front Sensor Low Reference	C0035 00	C0035 00	C0035 00	C0035 0F, 18
Right Front Sensor Signal	C0040 00	C0040 00	C0040 00	C0040 0F, 18
Right Front Sensor Low Reference	C0040 00	C0040 00	C0040 00	C0040 0F, 18
Left Rear Sensor Signal	C0045 00	C0045 00	C0045 00	C0045 0F, 18
Left Rear Sensor Low Reference	C0045 00	C0045 00	C0045 00	C0045 0F, 18
Right Rear Sensor Signal	C0050 00	C0050 00	C0050 00	C0050 0F, 18
Right Rear Sensor Low Reference	C0050 00	C0050 00	C0050 00	C0050 0F, 18

Circuit/System Description

As the wheel spins, the wheel speed sensor produces an AC signal. The electronic brake control module (EBCM) uses the frequency of the AC signal to calculate the wheel speed.

Conditions for Running the DTC

C0035-C0050 00

C0035-C0050 0F

C0035-C0050 18

Conditions for Setting the DTC

C0035-C0050 00

C0035-C0050 0F

The EBCM detects a rapid variation in the wheel speed. The wheel speed changes by 20 km/h (12 mph) or more in 0.01 second. The change must occur 3 times with no more than 0.2 seconds between occurrences.

C0035-C0050 18

OR

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. 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

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 15 km/h (10 mph).

Circuit/System Testing

It is recommended that Component Testing is performed before Circuit Testing when diagnosing wheel speed sensors.

1. Ignition OFF, disconnect the harness connector at the EBCM.
2. Ignition ON, test for 0 volts between the low reference circuit terminals of the appropriate sensor listed below and ground.

•	LF Sensor circuit terminal 8

•	RF Sensor circuit terminal 6

•	LR Sensor circuit terminal 2

•	RR Sensor circuit terminal 12

⇒	If not the specified value, test the low reference circuit for a short to voltage. If the circuit tests normal, replace the EBCM.

3. Test for 0 volts between the signal circuit terminals of the appropriate sensor listed below and ground.

•	LF Sensor circuit terminal 9

•	RF Sensor circuit terminal 5

•	LR Sensor circuit terminal 3

•	RR Sensor circuit terminal 11

⇒	If not the specified value, test the signal circuit for a short to voltage. If the circuit tests normal, replace the EBCM.

4. Ignition OFF, test for infinite resistance between the low reference terminals of the appropriate sensor listed below and ground.

•	LF Sensor circuit terminal 8

•	RF Sensor circuit terminal 6

•	LR Sensor circuit terminal 2

•	RR Sensor circuit terminal 12

⇒	If not the specified value, test the low reference circuit for a short to ground. If the circuit tests normal, replace the EBCM.

5. Test for infinite resistance between the following signal circuit terminals of the appropriate sensor listed below and ground.

•	LF Sensor circuit terminal 9

•	RF Sensor circuit terminal 5

•	LR Sensor circuit terminal 3

•	RR Sensor circuit terminal 11

⇒	If not the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the EBCM.

6. Test for 850-1350 ohms between the wheel speed sensor circuit terminals of the appropriate sensor listed below.

•	LF Sensor circuit terminals 8 and 9

•	RF Sensor circuit terminals 5 and 6

•	LR Sensor circuit terminals 2 and 3

•	RR Sensor circuit terminals 11 and 12

⇒	If not within the specified range, test the low reference and signal circuits for an open/high resistance. If the circuit tests normal, replace the wheel speed sensor.

7. If all circuits test normal, replace the EBCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.