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 or High Resistance	Short to Voltage	Signal Performance
Left Front Sensor Signal	C0035 00	C0035 00	C0035 00	C0035 0F C0035 18
Left Front Sensor Low Reference	C0035 00	C0035 00	C0035 00	C0035 0F C0035 18
Right Front Sensor Signal	C0040 00	C0040 00	C0040 00	C0040 0F C0040 18
Right Front Sensor Low Reference	C0040 00	C0040 00	C0040 00	C0040 0F C0040 18
Left Rear Sensor Signal	C0045 00	C0045 00	C0045 00	C0045 0F¹ C0045 18
Left Rear Sensor Low Reference	C0045 00	C0045 00	C0045 00	C0045 0F¹ C0045 18
Right Rear Sensor Signal	C0050 00	C0050 00	C0050 00	C0050 0F¹ C0050 18
Right Rear Sensor Low Reference	C0050 00	C0050 00	C0050 00	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 00 - C0050 00

C0035 0F - C0050 0F

C0035 18 - C0050 18

Conditions for Setting the DTC

C0035 00 - C0050 00

C0035 0F - 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 second between occurrences.

C0035 18 - C0050 18

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

Antilock Brake System Connector End Views

Electrical Information Reference

Scan Tool Reference

Scan Tool Data List for EBCM

Circuit/System Verification

Ignition ON, observe all the scan tool wheel speed sensors. The wheel speed sensors should display the same speed while driving in a straight line at a speed greater than 8 km/h (5 mph).

Circuit/System Testing

Important: Use the following list to identify the appropriate terminals to test at.

1. Ignition OFF, disconnect the harness connector at the EBCM.
2. Ignition ON, test for less than 1 volt between the appropriate wheel speed sensor signal circuit terminal and ground.

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

3. Ignition OFF, test for infinite resistance between the appropriate wheel speed sensor signal circuit terminal and ground.

⇒	If not the specified value, test the signal circuit and low reference circuit for a short to ground. If the circuits test normal, test or replace the wheel speed sensor.

4. Test for 850-1350 ohms of resistance between the appropriate wheel speed sensor signal circuit and low reference circuit.

⇒	If less than the specified range, test for a short between the signal circuit and low reference circuit. If the circuits test normal, test or replace the wheel speed sensor.

⇒	If greater than the specified range, test for an open/high resistance in the signal circuit and low reference circuit. If the circuits test normal, test or replace the wheel speed sensor.

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

Component Testing

1. Disconnect the wheel speed sensor connector.
2. With the ignition OFF, measure for 850-1350 ohms of resistance across the wheel speed sensor.

⇒	If the resistance is not between 850-1350 ohms, replace the faulty wheel speed sensor.

3. Spin the wheel, measure across the wheel speed sensor for 100 mv AC or greater.

⇒	If the AC voltage is less than 100 mv, replace the wheel speed sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.