C0046

DTC C0035-C0052

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.

DTC Descriptors
DTC C0035
- Left Front Wheel Speed Sensor Circuit

DTC C0036
- Left Front Wheel Speed Sensor Circuit Range/Performance

DTC C0037
- Left Front Wheel Speed Sensor Circuit Low

DTC C0040
- Right Front Wheel Speed Sensor Circuit

DTC C0041
- Right Front Wheel Speed Sensor Circuit Range/Performance

DTC C0042
- Right Front Wheel Speed Sensor Circuit Low

DTC C0045
- Left Rear Wheel Speed Sensor Circuit

DTC C0046
- Left Rear Wheel Speed Sensor Circuit Range/Performance

DTC C0047
- Left Rear Wheel Speed Sensor Circuit Low

DTC C0050
- Right Rear Wheel Speed Sensor Circuit

DTC C0051
- Right Rear Wheel Speed Sensor Circuit Range/Performance

DTC C0052
- Right Rear Wheel Speed Sensor Circuit Low

Circuit 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, C0040, C0045, or C0050

The ignition is ON.

C0036, C0037, C0041, C0042, C0046, C0047, C0051, or C0052
* DTCs C0035, C0040, C0045, or C0050 are not set.
* The brake pedal is not pressed.
* The ABS is not active.
* At least two wheel speeds are not 0 km/h.

Conditions for Setting the DTC

C0035, C0040, C0045, or C0050

The EBCM detects an open, short to ground or a short to power on the wheel speed sensor signal circuit or the low reference circuit.

C0036, C0041, C0046, or C0051

The EBCM detects a rapid variation in the wheel speed. The wheel speed changes by 16 km/h (10 mph) or more in 0.01 second. The change must occur 3 times with no more than 0.2 seconds between occurrences.

C0037, C0042, C0047, or C0052
* The suspect wheel speed equals zero.
* The other wheel speeds are greater than 8 km/h (5 mph).
* The other wheel speeds are within 11 km/h (7 mph) of each other.

Action Taken When the DTC Sets

If equipped, the following actions occur:

* The EBCM disables the ABS/traction control system (TCS)/vehicle stability enhancement system (VSES) for the duration of the ignition cycle.
* The dynamic rear proportion (DRP) does not function optimally.
* The ABS indicator turns ON.
* The Traction Control indicator turns ON.
* The driver information center (DIC) displays the Service Stability System message.

Conditions for Clearing the DTC

* The condition for the DTC is no longer present and the DTC is cleared with a scan tool.
* The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

Diagnostic Aids

C0035, C0037, C0040, C0042, C0045, C0047, C0050 or C0052

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 (9.9 ml) of salt to 354 ml (12 oz) 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. If the DTC returns, replace the suspected wheel speed sensor or repair the wheel speed sensor wiring.
4. Rinse the area thoroughly when completed.

C0036, C0041, C0046, or C0051

A possible cause of this DTC is electrical noise on the wheel speed sensor harness wiring. Electrical noise could result from the wheel speed sensor wires being routed to close to high energy ignition system components, such as spark plug wires.

Reference Information
Schematic Reference

Antilock Brake System Schematics ([1][2]Antilock Brakes / Traction Control Systems)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

ABS Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

Observe the scan tool Wheel Speed Sensor parameter. The reading should be the same 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 appropriate wheel speed sensor.
2. Test for 850-1350 ohms of resistance between terminal A and terminal B of the wheel speed sensor.

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

3. Test for greater than 100 mV AC voltage between terminal A and terminal B of the wheel speed sensor, when spinning the wheel.

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

4. Disconnect the harness connector at the EBCM.
5. Test for infinite resistance between the signal circuit terminal A and ground.

• If not the specified value, test the signal circuit for a short to ground.

6. Test for infinite resistance between the low reference circuit terminal B and ground.

• If not the specified value, test the low reference circuit for a short to ground.

7. Test for less than 1 ohm between the signal circuit terminal A at the wheel speed connector and the appropriate terminal 13, 27, 39, or 42 at the EBCM connector.

• If not within the specified range, test the signal circuit for an open or a high resistance.

8. Test for less than 1 ohm between the low reference circuit terminal B at the wheel speed sensor connector and the appropriate terminal 12, 24, 28, or 43 at the EBCM connector.

• If not within the specified range, test the low reference circuit for an open or a high resistance.

9. If all circuits test normal, replace the ECBM.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Front Wheel Speed Sensor Replacement (Front Wheel Speed Sensor Replacement)
* Rear Wheel Speed Sensor Replacement (Rear Wheel Speed Sensor Replacement)
* Control Module References (Programming and Relearning) for EBCM replacement, setup and programming