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 04: Left Front Wheel Speed Sensor Circuit Open CircuitDTC C1234: Left Rear Wheel Speed Sensor Circuit Open Circuit
DTC C0035 26: Left Front Wheel Speed Sensor Circuit Frequency too Low
DTC C1221: Left Front Wheel Speed Sensor Circuit Frequency too Low
DTC C0035 27: Left Front Wheel Speed Sensor Circuit Frequency too High
DTC C1225: Left Front Wheel Speed Sensor Circuit Frequency too High
DTC C0035 0E: Left Front Wheel Speed Sensor Circuit Resistance Below Threshold
DTC C1207: Left Front Wheel Speed Sensor Circuit Resistance Below Threshold
DTC C0035 1F: Left Front Wheel Speed Sensor Circuit Intermittent
DTC C1221: Left Front Wheel Speed Sensor Circuit Intermittent
DTC C0040 04: Right Front Wheel Speed Sensor Circuit Open Circuit
DTC C1233: Right Front Wheel Speed Sensor Circuit Open Circuit
DTC C0040 0E: Right Front Wheel Speed Sensor Circuit Resistance Below Threshold
DTC C1208: Right Front Wheel Speed Sensor Circuit Resistance Below Threshold
DTC C0040 1F: Right Front Wheel Speed Sensor Circuit Intermittent
DTC C1222: Right Front Wheel Speed Sensor Circuit Intermittent
DTC C0040 26: Right Front Wheel Speed Sensor Circuit Frequency too Low
DTC C1222: Right Front Wheel Speed Sensor Circuit Frequency too Low
DTC C0040 27: Right Front Wheel Speed Sensor Circuit Frequency too High
DTC C1226: Right Front Wheel Speed Sensor Circuit Frequency too High
DTC C0045 04: Left Rear Wheel Speed Sensor Circuit Open Circuit
DTC C1234: Left Rear Wheel Speed Sensor Circuit Open Circuit
DTC C0045 0E: Left Rear Wheel Speed Sensor Circuit Resistance Below Threshold
DTC C1209: Left Rear Wheel Speed Sensor Circuit Resistance Below Threshold
DTC C0045 1F: Left Rear Wheel Speed Sensor Circuit Intermittent
DTC C1223: Left Rear Wheel Speed Sensor Circuit Intermittent
DTC C0045 26: Left Rear Wheel Speed Sensor Circuit Frequency too Low
DTC C1223: Left Rear Wheel Speed Sensor Circuit Frequency too Low
DTC C0045 27: Left Rear Wheel Speed Sensor Circuit Frequency too High
DTC C1227: Left Rear Wheel Speed Sensor Circuit Frequency too High
DTC C0050 04: Right Rear Wheel Speed Sensor Circuit Open Circuit
DTC C1235: Right Rear Wheel Speed Sensor Circuit Open Circuit
DTC C0050 0E: Right Rear Wheel Speed Sensor Circuit Resistance Below Threshold
DTC C1210: Right Rear Wheel Speed Sensor Circuit Resistance Below Threshold
DTC C0050 1F: Right Rear Wheel Speed Sensor Circuit Intermittent
DTC C1224: Right Rear Wheel Speed Sensor Circuit Intermittent
DTC C0050 26: Right Rear Wheel Speed Sensor Circuit Frequency too Low
DTC C1224: Right Rear Wheel Speed Sensor Circuit Frequency too Low
DTC C0050 27: Right Rear Wheel Speed Sensor Circuit Frequency too High
DTC C1228: Right Rear Wheel Speed Sensor Circuit Frequency too High
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Left Front Wheel Speed Sensor 12 Volt Reference | C0035 04,C1232 | C0035 04,C1232 | C0035 0E,C1207 | C0035 1F,C1221, C0035 26,C1221 C0035 27,C1225 |
Left Front Wheel Speed Sensor Signal | C0035 04,C1232 | C0035 04,C1232 | C0035 0E,C1207 | C0035 1F,C1221, C0035 26,C1221 C0035 27,C1225 |
Right Front Wheel Speed Sensor 12 Volt Reference | C0040 04,C1233 | C0040 04,C1233 | -- | C0040 1F,C1222, C0040 26,C1222 C0040 27,C1226 |
Right Front Wheel Speed Sensor Signal | C0040 04,C1233 | C0040 04,C1233 | C0040 0E,C1208 | C0040 1F,C1222, C0040 26,C1222 C0040 27,C1226 |
Left Rear Wheel Speed Sensor 12 Volt Reference | C0045 0E,C1209 | C0045 04,C1234 | -- | C0045 1F,C1223, C0045 26,C1223 C0045 27,C1227 |
Left Rear Wheel Speed Sensor Signal | C0045 04,C1234 | C0045 04,C1234 | C0045 0E,C1209 | C0045 1F,C1223, C0045 26,C1223 C0045 27,C1227 |
Right Rear Wheel Speed Sensor 12 Volt Reference | C0050 04,C1235 | C0050 04,C1235 | -- | C0050 1F,C1224, C0050 26,C1224 C0050 27,C1228 |
Right Rear Wheel Speed Sensor Signal | C0050 04,C1235 | C0050 04,C1235 | C0050 0E,C1210 | C0050 1F,C1224, C0050 26,C1224 C0050 27,C1228 |
Component | Condition | DTCs | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Left Front Wheel Speed Sensor |
| C0035 1F,C1221, C0035 26,C1221 C0035 27,C1225 | ||||||||||
Right Front Wheel Speed Sensor |
| C0040 1F,C1222, C0040 26,C1222 C0040 27,C1226 | ||||||||||
Left Rear Wheel Speed Sensor |
| C0045 1F,C1223, C0045 26,C1223 C0045 27,C1227 | ||||||||||
Right Rear Wheel Speed Sensor |
| C0050 1F,C1224, C0050 26,C1224 C0050 27,C1228 |
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
| • | Ignition ON. |
| • | Ignition voltage is greater than 10 volts. |
| • | 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,C1232 - C1235, or C1207 - C1210
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, C1225 - C1228, or C1221 - C1224
| • | 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. |
Conditions for Setting the DTC
| • | A short to voltage, short to ground or an open/high resistance is detected on a wheel speed sensor circuit. |
| • | 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 DIC 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: 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:
- 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).
- Test drive the vehicle over various road surfaces: bumps, turns, etc., above 40 km/h (25 mph) for at least 30 seconds.
- Rinse the area thoroughly when completed.
Reference Information
Schematic Reference
Antilock Brake System Schematics
Connector End View Reference
Description and Operation
Electrical Information Reference
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
- Ignition OFF, disconnect the harness connector at the EBCM.
- Ignition ON, test for less than 1 volt between the 12-volt reference circuit terminal of the appropriate sensor listed below and ground.
- Test for less than 1 volt between the signal circuit terminal of the appropriate sensor listed below and ground.
- Ignition OFF, test for infinite resistance between the 12-volt reference terminal of the appropriate sensor circuit listed below and ground.
- Test for infinite resistance between the following signal circuit terminal of the appropriate sensor circuit listed below and ground.
- Ignition OFF, disconnect the harness connector at the appropriate WSS.
- Test for less than 2 ohms between the appropriate 12-volt reference circuit terminals listed below.
- Test for less than 2 ohms between the appropriate signal circuit terminals listed below.
- If all circuits test normal, replace the appropriate wheel speed sensor. If the DTC resets replace the EBCM.
| • | LF Sensor circuit terminal 28 |
| • | RF Sensor circuit terminal 17 |
| • | LR Sensor circuit terminal 4 |
| • | RR Sensor circuit terminal 3 |
| ⇒ | If greater than the specified range, test the low reference circuit for a short to voltage. |
| • | LF Sensor circuit terminal 29 |
| • | RF Sensor circuit terminal 6 |
| • | LR Sensor circuit terminal 5 |
| • | RR Sensor circuit terminal 2 |
| ⇒ | If greater than the specified range, test the signal circuit for a short to voltage. |
| • | LF Sensor circuit terminal 28 |
| • | RF Sensor circuit terminal 17 |
| • | LR Sensor circuit terminal 4 |
| • | RR Sensor circuit terminal 3 |
| ⇒ | If less than the specified value, test the 12- volt reference circuit for a short to ground. |
| • | LF Sensor circuit terminal 29 |
| • | RF Sensor circuit terminal 6 |
| • | LR Sensor circuit terminal 5 |
| • | RR Sensor circuit terminal 2 |
| ⇒ | If less than the specified value, test the signal circuit for a short to ground. |
| • | LF Sensor circuit terminal 28 at the EBCM harness connector, and terminal 2 at the WSS harness connector |
| • | RF Sensor circuit terminal 17 at the EBCM harness connector, and terminal 2 at the WSS harness connector |
| • | LR Sensor circuit terminal 4 at the EBCM harness connector, and terminal B at the WSS harness connector |
| • | RR Sensor circuit terminal 3 at the EBCM harness connector, and terminal B at the WSS harness connector |
| ⇒ | If greater than the specified range, test the 12-volt reference circuit for an open or high resistance. |
| • | LF Sensor circuit terminal 29 at the EBCM harness connector, and terminal 1 at the WSS harness connector |
| • | RF Sensor circuit terminal 6 at the EBCM harness connector, and terminal 1 at the WSS harness connector |
| • | LR Sensor circuit terminal 5 at the EBCM harness connector, and terminal A at the WSS harness connector |
| • | RR Sensor circuit terminal 2 at the EBCM harness connector, and terminal A at the WSS harness connector |
| ⇒ | If greater than the specified range, test the signal circuit for an open or high resistance. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for EBCM replacement, setup, and programming |
