GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 HUMMER 🢒 2009 🢒 H2 🢒 Driver Information and Entertainment 🢒 Cellular, Entertainment, and Navigation 🢒 DTC C0035-C0050

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 03: Left Front Wheel Speed Sensor Circuit Voltage Below Threshold

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

DTC C0040 03: Right Front Wheel Speed Sensor Circuit Voltage Below Threshold

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

DTC C0045 03: Left Rear Wheel Speed Sensor Circuit Voltage Below Threshold

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

DTC C0050 03: Right Rear Wheel Speed Sensor Circuit Voltage Below Threshold

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/High Resistance

Short to Voltage

Signal Performance

Left Front Sensor Signal

C0035

C0035

C0035

C0035 0F, C0035 18, C0035 03

Left Front Sensor Low Reference

C0035

C0035

C0035

C0035 0F, C0035 18

Right Front Sensor Signal

C0040

C0040

C0040

C0040 0F, C0040 18, C0040 03

Right Front Sensor Low Reference

C0040

C0040

C0040

C0040 0F, C0040 18

Left Rear Sensor Signal

C0045

C0045

C0045

C0045 0F, C0045 18, C0045 03

Left Rear Sensor Low Reference

C0045

C0045

C0045

C0045 0F, C0045 18

Right Rear Sensor Signal

C0050

C0050

C0050

C0050 0F, C0050 18, C0050 03

Right Rear Sensor Low Reference

C0050

C0050

C0050

C0050 0F, C0050 18

Circuit/System Description

The wheel speed sensor receives a 12-volt power supply voltage from the electronic brake control module (EBCM) and provides an output signal to the EBCM. As the wheel spins, the wheel speed sensor sends the EBCM a DC square wave signal. The EBCM uses the frequency of the square wave signal to calculate the wheel speed.

Conditions for Running the DTC

C0035-C0050

    • The ignition is ON.
    • Ignition voltage is greater than 9.5 volts.

C0035-C0050 0F

    • The ignition is ON.
    • Ignition voltage is greater than 9.5 volts.
    • The brake pedal is not pressed.
    • A DTC is not set for the other wheel speed circuit on the same axle.

C0035-C0050 18

    • The ignition is ON.
    • Ignition voltage is greater than 9.5 volts.
    • The brake pedal is not pressed.
    • No other wheel speed circuit DTCs are set.
    • At least 2 other wheel speeds are not 0 km/h.

Conditions for Setting the DTC

C0035-C0050

    • 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.

C0035-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-C0050 18

    • One wheel speed is 2 km/h (1.2 mph).
    • The remaining wheel speeds are greater than 10 km/h (6.2 mph).
    • The difference between the remaining wheel speeds is less than 8 km/h (5 mph) from each other for 180 seconds.

OR

    • The 2 wheel speed sensor inputs are 0 and DTCs are set.
    • The 2 suspect wheel speeds equal 0 for 6 seconds.
    • The other wheel speeds are greater than 15 km/h (10 mph).
    • The other wheel speeds are within 11 km/h (7 mph) of each other.

Action Taken When the DTC Sets
    • The EBCM disables the Antilock Brake System (ABS)/Traction Control System (TCS)/Vehicle Stability Enhancement System (VSES) for the duration of the ignition cycle.
    • A DIC message and/or a warning message may be displayed.
    • If both rear wheel speed DTCs are set, the dynamic rear proportioning (DRP) is disabled and the Brake Warning indicator turns ON.

Conditions for Clearing the MIL/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.
    • An ECE 13 response may occur. If an ECE 13 response is present the vehicle must be operated at a speed greater than 15 km/h (9 mph) to turn off the ABS warning lamp.

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. If the DTC returns, replace the suspected wheel speed sensor or repair the wheel speed sensor wiring.
  4. 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
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs
    •  Connector 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

Important: It is recommended that Component Testing is performed before Circuit Testing when diagnosing wheel speed sensors.

  1. Ignition OFF, disconnect the harness connector at the EBCM.
  2. Ignition ON, test for less than 1 volt between the low reference circuit terminals of the appropriate sensor listed below and ground.
    3. • LF Sensor circuit terminal 37
    • RF Sensor circuit terminal 6
    • LR Sensor circuit terminal 4
    • RR Sensor circuit terminal 35
    ⇒If greater than the specified value, test the low reference circuit for a short to voltage. If the circuit tests normal, replace the wheel speed sensor
  3. Test for less than 1 volt between the signal circuit terminals of the appropriate sensor listed below and ground.
    4. • LF Sensor circuit terminal 36
    • RF Sensor circuit terminal 5
    • LR Sensor circuit terminal 3
    • RR Sensor circuit terminal 34
    ⇒If greater than the specified value, test the signal circuit for a short to voltage. If the circuit tests normal, replace the wheel speed sensor.
  4. Ignition OFF, test for infinite resistance between the low reference terminals of the appropriate sensor listed below and ground.
    5. • LF Sensor circuit terminal 37
    • RF Sensor circuit terminal 6
    • LR Sensor circuit terminal 4
    • RR Sensor circuit terminal 35
    ⇒If less than the specified value, test the low reference circuit for a short to ground. If the circuit tests normal, test or replace the wheel speed sensor.
  5. Test for infinite resistance between the following signal circuit terminals of the appropriate sensor listed below and ground.
    6. • LF Sensor circuit terminal 36
    • RF Sensor circuit terminal 5
    • LR Sensor circuit terminal 3
    • RR Sensor circuit terminal 34
    ⇒If less than the specified value, test the signal circuit for a short to ground. If the circuit tests normal, test or replace the wheel speed sensor.
  6. Ignition OFF, disconnect the harness connector at the appropriate wheel speed sensor.
  7. Test for less than 2 ohms between the appropriate signal circuit terminals listed below.
    8. • LF Sensor circuit terminals 36 at the EBCM harness connector, and terminal 2 at the WSS harness connector
    • RF Sensor circuit terminals 5 at the EBCM harness connector, and terminal 2 at the WSS harness connector
    • LR Sensor circuit terminals 3 at the EBCM harness connector, and terminal B at the WSS harness connector
    • RR Sensor circuit terminals 34 at the EBCM harness connector, and terminal B at the WSS harness connector
    ⇒If greater than the specified value, test the signal circuit for an open or high resistance. If the circuit tests normal, test or replace the wheel speed sensor.
  8. Test for less than 2 ohms between the appropriate low reference circuit terminals listed below.
    9. • LF Sensor circuit terminals 37 at the EBCM harness connector, and terminal 1 at the WSS harness connector
    • RF Sensor circuit terminals 6 at the EBCM harness connector, and terminal 1 at the WSS harness connector
    • LR Sensor circuit terminals 4 at the EBCM harness connector, and terminal A at the WSS harness connector
    • RR Sensor circuit terminals 35 at the EBCM harness connector, and terminal A at the WSS harness connector
    ⇒If greater than the specified value, test the low reference circuit for an open or high resistance. If the circuit tests normal, test or replace the wheel speed sensor.
  9. If all circuits test normal, replace the EBCM.

Component Testing
  1. Ignition OFF, disconnect the harness connector at the wheel speed sensor.
  2. Connect a jumper wire between signal circuit on the harness side and the wheel speed sensor signal circuit terminal 2 on the front WSS or terminal B on the rear WSS.
  3. Connect a DMM between the low reference terminal 1 on the front WSS, or terminal A on the rear and ground. Set up the DMM to measure mA using the DC scale.
  4. Spin the wheel very slowly. Using the DMM MIN/MAX feature, test for 4-8 mA on the MIN capture and 12-16 mA on the MAX capture.
    5. ⇒If not within the specified range, replace the wheel speed sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for EBCM and BPMV replacement, setup, and programming