C0045
DTC C0035-C0050, C1207-C1210, C1221-C1228, or C1232-C1235
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 Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC C0035 04
- Left Front Wheel Speed Sensor Circuit Open Circuit
DTC C1232 00
- Left Front Wheel Speed Sensor Circuit Low Input
DTC C0035 26
- Left Front Wheel Speed Sensor Circuit Frequency too Low
DTC C1221 00
- Left Front Wheel Speed Sensor Circuit Malfunction
DTC C0035 27
- Left Front Wheel Speed Sensor Circuit Frequency too High
DTC C1225 00
- Left Front Wheel Speed Sensor Circuit Performance
DTC C0035 0E
- Left Front Wheel Speed Sensor Circuit Resistance Below Threshold
DTC C1207 00
- Left Front Wheel Speed Sensor Circuit High Input
DTC C0035 1F
- Left Front Wheel Speed Sensor Circuit Intermittent
DTC C1221 00
- Left Front Wheel Speed Sensor Circuit Malfunction
DTC C0040 04
- Right Front Wheel Speed Sensor Circuit Open Circuit
DTC C1233 00
- Right Front Wheel Speed Sensor Circuit Low Input
DTC C0040 0E
- Right Front Wheel Speed Sensor Circuit Resistance Below Threshold
DTC C1208 00
- Right Front Wheel Speed Sensor Circuit High Input
DTC C0040 1F
- Right Front Wheel Speed Sensor Circuit Intermittent
DTC C1222 00
- Right Front Wheel Speed Sensor Circuit Malfunction
DTC C0040 26
- Right Front Wheel Speed Sensor Circuit Frequency too Low
DTC C1222 00
- Right Front Wheel Speed Sensor Circuit Malfunction
DTC C0040 27
- Right Front Wheel Speed Sensor Circuit Frequency too High
DTC C1226 00
- Right Front Wheel Speed Sensor Circuit Performance
DTC C0045 04
- Left Rear Wheel Speed Sensor Circuit Open Circuit
DTC C1234 00
- Left Rear Wheel Speed Sensor Circuit Low Input
DTC C0045 0E
- Left Rear Wheel Speed Sensor Circuit Resistance Below Threshold
DTC C1209 00
- Left Rear Wheel Speed Sensor Circuit High Input
DTC C0045 1F
- Left Rear Wheel Speed Sensor Circuit Intermittent
DTC C1223 00
- Left Rear Wheel Speed Sensor Circuit Malfunction
DTC C0045 26
- Left Rear Wheel Speed Sensor Circuit Frequency too Low
DTC C1223 00
- Left Rear Wheel Speed Sensor Circuit Malfunction
DTC C0045 27
- Left Rear Wheel Speed Sensor Circuit Frequency too High
DTC C1227 00
- Left Rear Wheel Speed Sensor Circuit Performance
DTC C0050 04
- Right Rear Wheel Speed Sensor Circuit Open Circuit
DTC C1235 00
- Right Rear Wheel Speed Sensor Circuit Low Input
DTC C0050 0E
- Right Rear Wheel Speed Sensor Circuit Resistance Below Threshold
DTC C1210 00
- Right Rear Wheel Speed Sensor Circuit High Input
DTC C0050 1F
- Right Rear Wheel Speed Sensor Circuit Intermittent
DTC C1224 00
- Right Rear Wheel Speed Sensor Circuit Malfunction
DTC C0050 26
- Right Rear Wheel Speed Sensor Circuit Frequency too Low
DTC C1224 00
- Right Rear Wheel Speed Sensor Circuit Malfunction
DTC C0050 27
- Right Rear Wheel Speed Sensor Circuit Frequency too High
DTC C1228 00
- Right Rear Wheel Speed Sensor Circuit Performance
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
* Ignition ON.
* Ignition voltage is greater than 10 V.
* The brake pedal is not pressed.
* Two or three other wheel speeds are greater than 0 km/h.
Conditions for Setting the DTC
C0035 04-C0050 04, C0035 0E-C0050 0E, C1207-C1210, or C1232-C1235
A short to voltage, short to ground or an open/high resistance is detected on a wheel speed sensor circuit.
C0035 26-C0050 26, C0035 27-C0050 27, C0035 1F-C0050 1F, C1221-C1224, or C1225-C1228
* A missing wheel speed sensor signal.
* An erratic signal output of the wheel speed sensor is detected.
* The EBCM detects a change in wheel speed that exceeds 20 km/h (12 mph) between two 10 millisecond wheel speed samples.
Actions Taken when the DTC Sets
* The EBCM disables the antilock brake system (ABS), traction control and Stabilitrak for the duration of the ignition cycle.
* A driver information center message and/or a warning indicator may be displayed.
Conditions for Clearing the DTC
* The condition for the DTC is no longer present.
* 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.
* The EBCM clears the history DTC when a current DTC is not detected in 40 consecutive drive cycles.
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.
* If the customer comments that the ABS indicator is ON only during moist environmental conditions inspect the wheel speed sensor wiring for signs of water intrusion.
Reference Information
Schematic Reference
Antilock Brake System Schematics [1][2]Antilock Brakes / Traction Control Systems
Connector End View Reference
Component Connector End Views Hybrid/EV Battery Pack X1 A4
Description and Operation
ABS Description and Operation Description and Operation
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 Control Module References for scan tool information
Circuit/System Verification
1. Drive the vehicle in a straight line at a speed greater than 20 km/h (13 mph).
2. Verify all scan tool Wheel Speed Sensor parameters are within 1.6 km/h (1 mph) of each other.
• If any parameter is not within 1.6 km/h (1 mph) of each other.
Refer to Circuit/System Testing
• If each parameter is within 1.6 km/h (1 mph) of each other.
3. All OK.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the K17 electronic brake control module (EBCM).
2. Ignition ON, test for less than 1 V between the K17 EBCM harness connector terminals listed below and ground:
* Terminal 28 and terminal 29 for the B5LF left front wheel speed sensor
* Terminal 17 and terminal 6 for the B5RF right front wheel speed sensor
* Terminal 4 and terminal 5 for the B5LR left rear wheel speed sensor
* Terminal 3 and terminal 2 for the B5RR right rear wheel speed sensor
• If 1 V or greater
Repair the short to voltage on the circuit.
• If less than 1 V
3. Ignition OFF.
4. Test for infinite resistance between the K17 EBCM harness connector terminals listed below and ground:
* Terminal 28 and terminal 29 for the B5LF left front wheel speed sensor
* Terminal 17 and terminal 6 for the B5RF right front wheel speed sensor
* Terminal 4 and terminal 5 for the B5LR left rear wheel speed sensor
* Terminal 3 and terminal 2 for the B5RR right rear wheel speed sensor
• If less than infinite resistance
Repair the short to ground on the circuit.
• If infinite resistance
5. Test for less than 2 ohm between the B5 wheel speed sensor harness connector terminal 1 and the K17 EBCM harness connector terminal listed below:
* Terminal 28 for the B5LF left front wheel speed sensor
* Terminal 17 for the B5RF right front wheel speed sensor
* Terminal 4 for the B5LR left rear wheel speed sensor
* Terminal 3 for the B5RR right rear wheel speed sensor
• If 2 ohm or greater
Repair the open/high resistance in the circuit.
• If less than 2 ohm
6. Test for less than 2 ohm between the B5 wheel speed sensor harness connector terminal 2 and the K17 EBCM harness connector terminal listed below:
* Terminal 29 for the B5LF left front wheel speed sensor
* Terminal 6 for the B5RF right front wheel speed sensor
* Terminal 5 for the B5LR left rear wheel speed sensor
* Terminal 2 for the B5RR right rear wheel speed sensor
• If 2 ohm or greater
Repair the open/high resistance in the circuit.
• If less than 2 ohm
7. Replace the B5 wheel speed sensor that the DTC set for.
8. Clear the DTC, drive the vehicle above 40 km/h (25 mph).
• If the DTC resets
Replace the K17 EBCM.
• If the DTC did not reset
9. All OK.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Front Wheel Speed Sensor Replacement Front Wheel Speed Sensor Replacement
* Rear Wheel Speed Sensor Replacement Rear Wheel Speed Sensor Replacement
* Control Module References Control Module References for EBCM replacement, programming and setup