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C0041



DTC C0035-C0051

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 C0040
- Right Front Wheel Speed Sensor Circuit

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

DTC C0045
- Left Rear Wheel Speed Sensor Circuit

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

DTC C0050
- Right Rear Wheel Speed Sensor Circuit

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




Diagnostic Fault Information






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, C0040, C0045, C0050

The ignition is ON.


C0036, C0041, C0046, C0051
* The vehicle speed is over 40 km/h (25mph)
* The brake pedal is not pressed.
* The ABS is not active.



Conditions for Setting the DTC

C0035, C0040, C0045, C0050

One of the following conditions exists for 0.02 seconds:

* An open is detected on the wheel speed sensor signal circuit.
* A short to ground is detected on the wheel speed sensor signal circuit.
* A short to voltage is detected on the wheel speed sensor signal circuit.


C0036, C0041, C0046, C0051

All of the following conditions exists for 0.01 seconds:

* The suspect wheel speed sensor equals zero.
* The other wheel speeds are greater than 40 km/h (25mph) for 0.01 seconds.
* The suspect wheel equals zero during drive off, and the other wheels are greater than 18km/h (11mph).
* A short to ground the wheel speed sensor is shorted to ground
* A deviation of two wheel speed sensors at either side of the vehicle greater than 6km/h (4mph), or at the front axle greater than 10km/h (6mph) for a period of 10 to 20 seconds.



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.
* A DTC malfunction will set.
* The ABS indicator turns ON.
* The Stability Off indicator turns ON.
* The Red BRAKE Warning indicator could turn ON.



Conditions for Clearing the DTC

* The condition for setting 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

* A damaged rear wheel speed sensor ring can cause a DTC to set.
* If 2 or more wheel speed sensors are inoperative diagnose each wheel speed sensor individually.


C0035, C0040, C0045, C0050, C0051

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

Scan Tool Reference

Control Module References (Programming and Relearning) for Scan Tool Information


Circuit/System Verification

With scan tool installed drive the vehicle in a straight line at a speed greater than 40 km/h (25 mph), all wheel speed sensors should read the same km/h (mph). Verify in scan tool EBCM scan tool data.


Circuit/System Testing

Important: It is recommend that 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 volt between the sensor signal circuit terminal or the low reference circuit terminal and ground at the EBCM connector.

• If over 0 volt, repair short to voltage or shorted together in sensor signal circuit or the low reference circuit.

3. With the ignition OFF, measure for infinite ohms of resistance between the wheel speed sensor signal or 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 800-1600 ohms of resistance between the wheel speed sensor signal and low reference circuits at the EBCM connector.

• If greater than 1600 ohms test for an open/high resistance in the circuit or faulty wheel speed sensor.


• If less than 800 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. Disconnect the wheel speed sensor connector.
2. With the ignition OFF, measure for 800-1600 ohms of resistance across the wheel speed sensor.

• If the resistance is not between 800-1600 ohms replace the faulty wheel speed sensor.

3. Spin the wheel, with a scan tool measure the AC voltage across the wheel speed sensor for 100 mv AC or greater.

• If the AC voltage is less than 100 mv replace the faulty wheel speed sensor.




Repair Instructions

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

* Front Wheel Bearing and Hub Replacement (Front Suspension)
* Rear Wheel Bearing and Hub Replacement (Rear Suspension)
* Control Module References (Programming and Relearning) for EBCM replacement, setup, and programming


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