Diagnostic Instructions

DTC Descriptors

DTC C0035 02: Left Front Wheel Speed Sensor Circuit Short to Ground

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 02: Right Front Wheel Speed Sensor Circuit Short to Ground

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 02: Left Rear Wheel Speed Sensor Circuit Short to Ground

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 02: Right Rear Wheel Speed Sensor Circuit Short to Ground

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 or High Resistance	Short to Voltage	Signal Performance
Left Front Sensor Signal	C0035 02	--	--	C0035 0F, C0035 18
Left Front Sensor Low Reference	C0035 02	--	--	C0035 0F, C0035 18
Right Front Sensor Signal	C0040 02	--	--	C0040 0F, C0040 18
Right Front Sensor Low Reference	C0040 02	--	--	C0040 0F, C0040 18
Left Rear Sensor Signal	C0045 02	--	--	C0045 0F¹, C0045 18
Left Rear Sensor Low Reference	C0045 02	--	--	C0045 0F¹, C0045 18
Right Rear Sensor Signal	C0050 02	--	--	C0050 0F¹, C0050 18
Right Rear Sensor Low Reference	C0050 02	--	--	C0050 0F¹, C0050 18
¹Damaged rear wheel speed sensor ring can cause code to set.

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 02-C0050 02

C0035 0F-C0050 0F

C0035 18-C0050 18

Conditions for Setting the DTC

C0035 02-C0050 02 Open or Shorted Signal

A short to B+, short to ground, or an open/high resistance on the wheel speed sensor signal circuit.

C0035 0F-C0050 0F Erratic Signal or Sensor Dropout

Detects a missing sensor signal when the vehicle has been in motion with all sensors working.

Sensor Dropout

OR

Erratic Signal

C0035 18-C0050 18 Missing Sensor

Detects a missing sensor signal (or signals) when the vehicle accelerates from a standstill.

OR

Action Taken When the DTC Sets

Conditions for Clearing the MIL/DTC

Diagnostic Aids

C0035 18, 0F, 00-C0050 18, 0F, 00

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.
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

Ignition ON, observe the scan tool Wheel Speed Sensor parameter while driving, the vehicle in a straight line at a speed greater than 8 km/h (5 mph), all wheel speed sensor scan tool readings should read the same speed.

Circuit/System Testing

Important: Component Testing is performed before Circuit Testing when diagnosing wheel speed sensors.

1. With the ignition OFF, disconnect the EBCM connector.
2. With the ignition ON, measure for 0 volts between the sensor signal circuit terminal and the low reference circuit and ground at the EBCM connector.

⇒	If over 0 volts, repair short to voltage in sensor signal circuit or the low reference circuit.

3. With the ignition OFF, measure for infinite ohms between the wheel speed sensor signal and the low reference circuit and ground at the EBCM connector.

⇒	If less than infinite ohms, repair short to ground in the sensor signal or the low reference circuit.

4. Measure for 850-1350 ohms between the wheel speed sensor signal and low reference circuits at the EBCM connector.

⇒	If greater than 1350 ohms test for an open/high resistance in the circuit or faulty wheel speed sensor.

⇒	If less than 850 ohms test for a short between the circuits or faulty wheel speed sensor.

5. If all circuits test normal replace the EBCM.

Component Testing

1. Ignition OFF, disconnect the harness connector at the appropriate wheel speed sensor.
2. Test for 850-1350 ohms between the signal terminal A and the low reference signal terminal B. During the test, check for an intermittent circuit condition by gentle moving the wheel speed sensor pigtail harness.

⇒	If not within the specified range, replace the wheel speed sensor.

3. Test for infinite resistance between each terminal and the steering knuckle. Reverse the test leads, test for infinite resistance between each terminal and the steering knuckle again.

⇒	If less than the specified value, replace the appropriate wheel speed sensor.

4. Spin the wheel while monitoring the voltage between the signal terminal A and the low reference terminal B. The voltage should be greater than 100 mV AC.

⇒	If less than the specified range, replace the wheel speed sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.