Antilock Brake System - Non-Hybrid Greater than/Equal to 3900 kg (8600 lb) GVW
DTC C0035-C0050
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructionsprovides an overview of each diagnostic category.
DTC Descriptors
DTC C0035 02
- Left Front Wheel Speed Sensor Circuit Short to Ground
DTC C0035 05
- Left Front Wheel Speed Sensor Circuit Short to Battery or Open
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 05
- Right Front Wheel Speed Sensor Circuit Short to Battery or Open
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 05
- Left Rear Wheel Speed Sensor Circuit Short to Battery or Open
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 05
- Right Rear Wheel Speed Sensor Circuit Short to Battery or Open
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/System Description
The wheel speed sensor receives ignition voltage from the electronic brake control module (EBCM) and provides a DC square wave signal back to the module. As the wheel spins, the EBCM uses the frequency of the square wave signal to calculate the wheel speed.
Conditions for Running the DTC
C0035 02 and 05-C0050 02 and 05
Ignition ON.
C0035 18-C0050 18
* Ignition ON.
* No other wheel speed circuit DTCs are set.
* The brake pedal is not pressed.
* Two or three other wheel speeds are greater than 0 km/h.
C0035 0F-C0050 0F
* Ignition ON.
* The brake pedal is not pressed.
* A DTC is not set for the other wheel speed circuit on the same axle.
Conditions for Setting the DTC
C0035 02-C0050 02
A short to ground is detected on the wheel speed 12-volt reference or signal circuit.
C0035 05-C0050 05
A short to voltage, or an open is detected on 12-volt reference or the signal circuit.
C0035 0F-C0050 0F
* An erratic signal output of the wheel speed sensor is detected 3 times in 200 milliseconds.
* The EBCM detects a change in wheel speed that exceeds 20 km/h (12 mph) between two 10 millisecond wheel speed samples. This must be detected 3 times in 200 milliseconds.
* A missing wheel speed sensor signal
Actions Taken when the DTC Sets
* The EBCM disables the antilock brake system (ABS) and StabiliTrak for the duration of the ignition cycle.
* The ABS indicator turns ON.
* The traction control off indicator turns ON.
Conditions for Clearing the DTC
* A current DTC clears when the diagnostic runs and passes.
* A history DTC clears after 100 consecutive ignition cycles, if no failures are reported.
Diagnostic Aids
* Inspect the back of the wheel bearing on the encoder surface for metal debris that could cause an erratic reading with the sensor. Do not use a magnet to clean the debris, or damage to the encoder ring may occur.
* If 2 or more wheel speed sensors are inoperative diagnose each wheel speed sensor individually.
* An ECE 13 response may be required, after repairs are made, and DTCs are cleared, operate the vehicle at speeds greater than 15 km/h (10 mph) to complete the self test, and the EBCM will turn off the ABS indicator.
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 Non-Hybrid Greater than/Equal to 3900 kg (8600 lb) GVW
Connector End View Reference
Component Connector End Views Connector End Views By Name
Description and Operation
ABS Description and Operation ABS (Non-Hybrid Greater than/Equal to 3900 kg (8600 lb) GVW)
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
Scan Tool Reference
Control Module References Programming and Relearningfor 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 20 km/h (13 mph).
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the EBCM.
2. Ignition ON, test for less than 1 V between the 12 V reference circuit terminal of the appropriate sensor listed below and ground.
* Left Front Sensor circuit terminal 28
* Right Front Sensor circuit terminal 17
* Left Rear Sensor circuit terminal 4
* Right Rear Sensor circuit terminal 3
• If greater than the specified value, test the 12 V reference circuit for a short to voltage.
3. Test for less than 1 V between the signal circuit terminal of the appropriate sensor listed below and ground.
* Left Front Sensor circuit terminal 29
* Right Front Sensor circuit terminal 6
* Left Rear Sensor circuit terminal 5
* Right Rear Sensor circuit terminal 2
• If greater than the specified value, test the signal circuit for a short to voltage.
4. Ignition OFF, test for infinite resistance between the 12 V reference terminal of the appropriate sensor listed below and ground.
* Left Front Sensor circuit terminal 28
* Right Front Sensor circuit terminal 17
* Left Rear Sensor circuit terminal 4
* Right Rear Sensor circuit terminal 3
• If less than the specified value, test the 12 V reference circuit for a short to ground.
5. Test for infinite resistance between the following signal circuit terminal of the appropriate sensor listed below and ground.
* Left Front Sensor circuit terminal 29
* Right Front Sensor circuit terminal 6
* Left Rear Sensor circuit terminal 5
* Right Rear Sensor circuit terminal 2
• If less than the specified value, test the signal circuit for a short to ground.
6. Ignition OFF, disconnect the harness connector at the appropriate wheel speed sensor.
7. Test for less than 2 ohm between the appropriate 12 V reference circuit terminals listed below.
* Left Front Sensor circuit terminals 28 at the EBCM harness connector, and terminal 2 at the wheel speed sensor harness connector
* Right Front Sensor circuit terminals 17 at the EBCM harness connector, and terminal 2 at the wheel speed sensor harness connector
* Left Rear Sensor circuit terminals 4 at the EBCM harness connector, and terminal B at the wheel speed sensor harness connector
* Right Rear Sensor circuit terminals 3 at the EBCM harness connector, and terminal B at the wheel speed sensor harness connector
• If greater than the specified value, test the 12 V reference circuit for an open or high resistance.
8. Test for less than 2 ohm between the appropriate signal circuit terminals listed below.
* Left Front Sensor circuit terminals 29 at the EBCM harness connector, and terminal 1 at the wheel speed sensor harness connector
* Right Front Sensor circuit terminals 6 at the EBCM harness connector, and terminal 1 at the wheel speed sensor harness connector
* Left Rear Sensor circuit terminals 5 at the EBCM harness connector, and terminal A at the wheel speed sensor harness connector
* Right Rear Sensor circuit terminals 2 at the EBCM harness connector, and terminal A at the wheel speed sensor harness connector
• If greater than the specified value, test the signal circuit for an open or high resistance.
9. If all circuits test normal, replace the appropriate wheel speed sensor. If the DTC resets replace the EBCM.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Front Wheel Speed Sensor Replacement Service and Repair
* Rear Wheel Speed Sensor Replacement Service and Repair
* Control Module References Programming and Relearningfor EBCM replacement, setup, and programming