For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptors

DTC C0035 00: Left Front Wheel Speed Sensor Circuit
DTC C0035 5A: Left Front Wheel Speed Sensor Circuit Plausibility Failure
DTC C0040 00: Right Front Wheel Speed Sensor Circuit
DTC C0040 5A: Right Front Wheel Speed Sensor Circuit Plausibility Failure
DTC C0045 00: Left Rear Wheel Speed Sensor Circuit
DTC C0045 5A: Left Rear Wheel Speed Sensor Circuit Plausibility Failure
DTC C0050 00: Right Rear Wheel Speed Sensor Circuit
DTC C0050 5A: Right Rear Wheel Speed Sensor Circuit Plausibility Failure

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Left Front Wheel Speed Sensor 12-Volt Reference | C0035 00 | C0035 00 | -- | C0035 5A
Left Front Wheel Speed Sensor Signal | C0035 00 | C0035 00 | C0035 00 | C0035 5A
Right Front Wheel Speed Sensor 12-Volt Reference | C0040 00 | C0040 00 | -- | C0040 5A
Right Front Wheel Speed Sensor Signal | C0040 00 | C0040 00 | C0040 00 | C0040 5A
Left Rear Wheel Speed Sensor 12-Volt Reference | C0045 00 | C0045 00 | -- | C0045 5A
Left Rear Wheel Speed Sensor Signal | C0045 00 | C0045 00 | C0045 00 | C0045 5A
Right Rear Wheel Speed Sensor 12 Volt Reference | C0050 00 | C0050 00 | -- | C0050 5A
Right Rear Wheel Speed Sensor Signal | C0050 00 | C0050 00 | C0050 00 | C0050 5A

Component | Condition | DTCs
--- | --- | ---
Left Front Wheel Speed Sensor |

• | Physical damage

• | Debris on the wheel speed sensor or the encoder ring

• | Loose or improperly mounted sensor

• | Loose or worn wheel bearing

• | Air gap between the wheel speed sensor and the encoder ring too large

C0035 5A

Right Front Wheel Speed Sensor |

• | Physical damage

• | Debris on the wheel speed sensor or the encoder ring

• | Loose or improperly mounted sensor

• | Loose or worn wheel bearing

• | Air gap between the wheel speed sensor and the encoder ring too large

C0040 5A

Left Rear Wheel Speed Sensor |

• | Physical damage

• | Debris on the wheel speed sensor or the encoder ring

• | Loose or improperly mounted sensor

• | Loose or worn wheel bearing

• | Air gap between the wheel speed sensor and the encoder ring too large

C0045 5A

Right Rear Wheel Speed Sensor |

• | Physical damage

• | Debris on the wheel speed sensor or the encoder ring

• | Loose or improperly mounted sensor

• | Loose or worn wheel bearing

• | Air gap between the wheel speed sensor and the encoder ring too large

C0050 5A

### Circuit/System Description

The wheel speed sensor (WSS) 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 00-C0050 00

• | Ignition ON.

• | Ignition voltage is greater than 10 volts.

#### C0035 5A-C0050 5A

• | Ignition ON.

• | Ignition voltage is greater than 10 volts.

• | The brake pedal is not pressed.

• | A DTC is not set for the other wheel speed sensor on the same axle.

### Conditions for Setting the DTC

#### C0035 00-C0050 00

• | A short to ground, or an open/high resistance is detected on the wheel speed sensor 12-volt reference circuit.

• | A short to voltage, short to ground or an open/high resistance is detected on the signal circuit.

• | Wheel speed sensor power supply is less than 7.6 volts.

• | A missing wheel speed sensor signal

#### C0035 5A-C0050 5A

An erratic signal output of the wheel speed sensor is detected.

### Action Taken When the DTC Sets

• | The EBCM disables the antilock brake system (ABS)/traction control system (TCS) and vehicle stability enhancement system (VSES) for the duration of the ignition cycle.

• | A DIC message and/or a warning indicator may be displayed.

### Conditions for Clearing the DTC

• | A current DTC clears when the diagnostic runs and passes.

• | 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.

• | A history DTC clears after 100 consecutive ignition cycles, if no failures are reported by this diagnostic.

### Diagnostic Aids

If 2 or more wheel speed sensors are inoperative diagnose each wheel speed sensor individually.

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

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for 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 volt between the 12-volt reference circuit terminal of the appropriate sensor listed below and ground:

• | LF Sensor circuit terminal 26

• | RF Sensor circuit terminal 9

• | LR Sensor circuit terminal 6

• | RR Sensor circuit terminal 7

⇒ | If greater than the specified range, test the 12-volt reference circuit for a short to voltage.

3. Test for less than 1 volt between the signal circuit terminal of the appropriate sensor listed below and ground:

• | LF Sensor circuit terminal 5

• | RF Sensor circuit terminal 10

• | LR Sensor circuit terminal 27

• | RR Sensor circuit terminal 8

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

4. Ignition OFF, test for infinite resistance between the 12- volt reference terminal of the appropriate sensor circuit listed below and ground:

• | LF Sensor circuit terminal 26

• | RF Sensor circuit terminal 9

• | LR Sensor circuit terminal 6

• | RR Sensor circuit terminal 7

⇒ | If less than the specified value, test the 12-volt reference circuit for a short to ground.

5. Test for infinite resistance between the following signal circuit terminal of the appropriate sensor circuit listed below and ground:

• | LF Sensor circuit terminal 5

• | RF Sensor circuit terminal 10

• | LR Sensor circuit terminal 27

• | RR Sensor circuit terminal 8

⇒ | 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 WSS.
7. Test for less than 2 ohms between the appropriate 12-volt reference circuit terminals listed below:

• | LF Sensor circuit terminal 26 at the EBCM harness connector, and terminal 2 at the WSS harness connector

• | RF Sensor circuit terminal 9 at the EBCM harness connector, and terminal 2 at the WSS harness connector

• | LR Sensor circuit terminal 6 at the EBCM harness connector, and terminal 2 at the WSS harness connector

• | RR Sensor circuit terminal 7 at the EBCM harness connector, and terminal 2 at the WSS harness connector

⇒ | If greater than the specified range, test the 12-volt reference circuit for an open or high resistance.

8. Test for less than 2 ohms between the appropriate signal circuit terminals listed below:

• | LF Sensor circuit terminal 5 at the EBCM harness connector, and terminal 1 at the WSS harness connector

• | RF Sensor circuit terminal 10 at the EBCM harness connector, and terminal 1 at the WSS harness connector

• | LR Sensor circuit terminal 27 at the EBCM harness connector, and terminal 1 at the WSS harness connector

• | RR Sensor circuit terminal 8 at the EBCM harness connector, and terminal 1 at the WSS harness connector

⇒ | If greater than the specified range, 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 after completing the diagnostic procedure.

• | Front Wheel Speed Sensor Replacement

• | Rear Wheel Speed Sensor Replacement

• | Control Module References for EBCM replacement, setup, and programming