GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2009 🢒 Regal 🢒 Brakes 🢒 Antilock Brake System 🢒 DTC C0035, C0040, C0045, or 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 06: Left Front Wheel Speed Sensor Circuit Low Voltage/Open

DTC C0035 0F: Left Front Wheel Speed Sensor Circuit Erratic

DTC C0035 18: Left Front Wheel Speed Sensor Circuit Low Signal Amplitude

DTC C0035 5A: Left Front Wheel Speed Sensor Circuit Not Plausible

DTC C0040 06: Right Front Wheel Speed Sensor Circuit Low Voltage/Open

DTC C0040 0F: Right Front Wheel Speed Sensor Circuit Erratic

DTC C0040 18: Right Front Wheel Speed Sensor Circuit Low Signal Amplitude

DTC C0040 5A: Right Front Wheel Speed Sensor Circuit Not Plausible

DTC C0045 06: Left Rear Wheel Speed Sensor Circuit Low Voltage/Open

DTC C0045 0F: Left Rear Wheel Speed Sensor Circuit Erratic

DTC C0045 18: Left Rear Wheel Speed Sensor Circuit Low Signal Amplitude

DTC C0045 5A: Left Rear Wheel Speed Sensor Circuit Not Plausible

DTC C0050 06: Right Rear Wheel Speed Sensor Circuit Low Voltage/Open

DTC C0050 0F: Right Rear Wheel Speed Sensor Circuit Erratic

DTC C0050 18: Right Rear Wheel Speed Sensor Circuit Low Signal Amplitude

DTC C0050 5A: Right Rear Wheel Speed Sensor Circuit Not Plausible

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Left Front Wheel Speed Sensor 12 V Reference

C0035 06

C0035 5A

C0035 06

C0035 0F, C0035 18

Left Front Wheel Speed Sensor Low Reference

C0035 06

C0035 5A

C0035 06

C0035 0F, C0035 18

Right Front Wheel Speed Sensor 12 V Reference

C0040 06

C0040 5A

C0040 06

C0040 0F, C0040 18

Right Front Wheel Speed Sensor Low Reference

C0040 06

C0040 5A

C0040 06

C0040 0F, C0040 18

Left Rear Wheel Speed Sensor 12 V Reference

C0045 06

C0045 5A

C0045 06

C0045 0F, C0045 18

Left Rear Wheel Speed Sensor Low Reference

C0045 06

C0045 5A

C0045 06

C0045 0F, C0045 18

Right Rear Wheel Speed Sensor 12 V Reference

C0050 06

C0050 5A

C0050 06

C0050 0F, C0050 18

Right Rear Wheel Speed Sensor Low Reference

C0050 06

C0050 5A

C0050 06

C0050 0F, C0050 18

Component

Condition

DTCs

Left Front Wheel Speed Sensor
    • Physical damage
    • Debris on the wheel speed sensor or the encoder ring
    • Looseness
    • Air gap between the wheel speed sensor and the encoder ring too large
    • Water intrusion in the wiring harness

C0035 06, C0035 0F, C0035 18, C0035 5A

Right Front Wheel Speed Sensor
    • Physical damage
    • Debris on the wheel speed sensor or the encoder ring
    • Looseness
    • Air gap between the wheel speed sensor and the encoder ring too large
    • Water intrusion in the wiring harness

C0040 06, C0040 0F, C0040 18, C0040 5A

Left Rear Wheel Speed Sensor
    • Physical damage
    • Water intrusion in the wiring harness

C0045 06, C0045 0F, C0045 18, C0045 5A

Right Rear Wheel Speed Sensor
    • Physical damage
    • Water intrusion in the wiring harness

C0050 06, C0050 0F, C0050 18, C0050 5A

Circuit/System Description

The wheel speeds are detected by active wheel speed sensors and encoder rings. The encoder ring consists of permanent magnets. Each wheel speed sensor receives a 12 V reference voltage from the electronic brake control module (EBCM) and provides an alternating current square wave signal to the EBCM. 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 06, C0040 06, C0045 06, and C0050 06

Ignition ON

C0035 0F, C0040 0F, C0045 0F, and C0050 0F

    • Ignition ON
    • Vehicle speed is greater than 12.9 km/h (8 MPH)

C0035 18, C0040 18, C0045 18, and C0050 18

    • Ignition ON
    • Vehicle speed is greater than 6 km/h (3.7 MPH)

C0035 5A, C0040 5A, C0045 5A, and C0050 5A

    • Ignition ON
    • Vehicle speed is greater than 1.5 km/h (0.9 MPH)

Conditions for Setting the DTC

C0035 06, C0040 06, C0045 06, and C0050 06

A short to voltage or short to ground on the wheel speed sensor 12 V reference or low reference circuit is detected for 0.1 s.

C0035 0F, C0040 0F, C0045 0F, and C0050 0F

An erratic wheel speed sensor signal is detected.

C0035 18, C0040 18, C0045 18, and C0050 18

A missing wheel speed sensor signal is detected for 3-10 s.

C0035 5A, C0040 5A, C0045 5A, and C0050 5A

An open/high resistance on the wheel speed sensor 12 V reference or low reference circuit is detected for 0.75-3.75 s.

Action Taken When the DTC Sets
    • The EBCM disables the ABS, traction control, stability control and hill start assist for the duration of the ignition cycle.
    • The ABS indicator turns ON.
    • The traction control/stability control-active indicator turns ON.

Conditions for Clearing the DTC
    • A current DTC clears when the diagnostic runs and passes.
    • The EBCM will turn OFF the indicator in the next ignition cycle.

Diagnostic Aids
    • Do not use a magnet to clean the encoder ring.
    • 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% saltwater solution.
  2. Test drive the vehicle over various road surfaces (bumps, turns, etc.), above 40 km/h (25 MPH) for at least 30 s.
  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

Ignition ON, observe the scan tool Wheel Speed Sensor parameters. 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. Inspect the appropriate wheel speed sensor for contamination, physical damage and correct installation.
    2. ⇒If contamination, physical damage or incorrect installation is diagnosed, repair or replace the wheel speed sensor.
  2. Ignition OFF, disconnect the harness connector at the K17 Electronic Brake Control Module (EBCM) and at the appropriate wheel speed sensor.
  3. Ignition ON, test for less than 0.3 V between the appropriate circuit terminal listed below and ground:
    4. • Left front wheel speed sensor low reference circuit terminal 28 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Right front wheel speed sensor low reference circuit terminal 4 at theK17 Electronic Brake Control Module (EBCM) harness connector
    • Left rear wheel speed sensor low reference circuit terminal 35 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Right rear wheel speed sensor low reference circuit terminal 10 at the K17 Electronic Brake Control Module (EBCM) harness connector
    ⇒If greater than the specified value, test the low reference circuit for a short to voltage.
  4. Test for less than 0.3 V between the appropriate circuit terminal listed below and ground:
    5. • Left front wheel speed sensor 12 V reference circuit terminal 27 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Right front wheel speed sensor 12 V reference circuit terminal 3 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Left rear wheel speed sensor 12 V reference circuit terminal 36 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Right rear wheel speed sensor 12 V reference circuit terminal 11 at the K17 Electronic Brake Control Module (EBCM) harness connector
    ⇒If greater than the specified value, test the 12 V reference circuit for a short to voltage.
  5. Ignition OFF, test for infinite resistance between the appropriate circuit terminal listed below and ground:
    6. • Left front wheel speed sensor low reference circuit terminal 28 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Right front wheel speed sensor low reference circuit terminal 4 at theK17 Electronic Brake Control Module (EBCM) harness connector
    • Left rear wheel speed sensor low reference circuit terminal 35 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Right rear wheel speed sensor low reference circuit terminal 10 at the K17 Electronic Brake Control Module (EBCM) harness connector
    ⇒If less than the specified value, test the low reference circuit for a short to ground.
  6. Test for infinite resistance between the appropriate circuit terminal listed below and ground:
    7. • Left front wheel speed sensor 12 V reference circuit terminal 27 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Right front wheel speed sensor 12 V reference circuit terminal 3 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Left rear wheel speed sensor 12 V reference circuit terminal 36 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Right rear wheel speed sensor 12 V reference circuit terminal 11 at the K17 Electronic Brake Control Module (EBCM) harness connector
    ⇒If less than the specified value, test the 12 V reference circuit for a short to ground.
  7. Test for infinite resistance between the appropriate circuit terminals listed below:
    8. • Left front wheel speed sensor 12 V reference circuit terminal 27 and low reference circuit terminal 28 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Right front wheel speed sensor 12 V reference circuit terminal 3 and low reference circuit terminal 4 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Left rear wheel speed sensor 12 V reference circuit terminal 36 and low reference circuit terminal 35 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Right rear wheel speed sensor 12 V reference circuit terminal 11 and low reference circuit terminal 10 at the K17 Electronic Brake Control Module (EBCM) harness connector
    ⇒If less than the specified value, test the 12 V reference circuit and the low reference circuit for a short circuit.
  8. Connect the harness connector at the K17 Electronic Brake Control Module (EBCM).
  9. Ignition ON, test for greater than 11 V between the 12 V reference circuit terminal 1 at the harness connector of the appropriate wheel speed sensor and ground.
    10. ⇒If less than the specified value, test the 12 V reference circuit for an open/high resistance. If the circuit tests normal, replace the K17 Electronic Brake Control Module (EBCM).
  10. Test for greater than 11 V between the 12 V reference circuit terminal 1 and the low reference circuit terminal 2 at the harness connector of the appropriate wheel speed sensor.
    11. ⇒If less than the specified value, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K17 Electronic Brake Control Module (EBCM).
  11. If all circuits test normal, test the appropriate wheel speed sensor.

Component Testing

Note: Circuit/System Testing must be performed before Component Testing.

Dynamic Test

  1. Ignition OFF, connect the harness connector at the wheel speed sensor.
  2. Disconnect the harness connector at the K17 Electronic Brake Control Module (EBCM).
  3. Connect a fused jumper wire between B+ and the appropriate circuit terminal listed below:
    4. • Left front wheel speed sensor 12 V reference circuit terminal 27 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Right front wheel speed sensor 12 V reference circuit terminal 3 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Left rear wheel speed sensor 12 V reference circuit terminal 36 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Right rear wheel speed sensor 12 V reference circuit terminal 11 at the K17 Electronic Brake Control Module (EBCM) harness connector
  4. Spin the wheel very slowly, test for alternating current between ca. 7 mA and ca. 14 mA between the appropriate circuit terminal listed below and ground:
    5. • Left front wheel speed sensor low reference circuit terminal 28 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Right front wheel speed sensor low reference circuit terminal 4 at theK17 Electronic Brake Control Module (EBCM) harness connector
    • Left rear wheel speed sensor low reference circuit terminal 35 at the K17 Electronic Brake Control Module (EBCM) harness connector
    • Right rear wheel speed sensor low reference circuit terminal 10 at the K17 Electronic Brake Control Module (EBCM) harness connector
    ⇒If not within the specified range, replace the wheel speed sensor.

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