Diagnostic Instructions
| • | Perform the 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 C0460 00 : Steering Position SignalDTC C0460 39 : Steering Position Signal
DTC C0460 42 : Steering Position Signal Initialization Not Accomplished
DTC C0460 4B : Steering Position Signal Calibration Not Accomplished
DTC C0460 5A : Steering Position Signal Not Plausible
DTC C0460 71 : Steering Position Signal Internal Failure
DTC C0460 72 : Steering Position Signal Rolling Count Invalid
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Steering Wheel Position Sensor 12 Volt Reference Voltage | C0292 | C0292 | C0292 | -- |
Low Reference | C0460 00 | C0460 00 | -- | -- |
Steering Wheel Position Signal Can HI | C0460 00 | C0460 00 | -- | C0460 42, 4B, 5A, 71, 72 |
Steering Wheel Position Signal Can Lo | C0460 00 | C0460 00 | -- | C0460 42, 4B, 5A, 71, 72 |
Circuit/System Description
The steering angle sensor shares a 12-volt ignition supply voltage with the electronic brake control module (EBCM) and the yaw-rate/lateral sensor. The EBCM applies a ground to the steering angle sensor low reference circuit, which is shared with the yaw-rate/lateral sensor. If equipped, this vehicle received the steering wheel position signal from the power steering control module (PSCM) over GMLAN.
The steering angle sensor provides a GMLAN signal output to the EBCM that represents the steering wheel degree of rotation. The EBCM utilizes this signal to calculate the driver intended driving direction.
Conditions for Running the DTC
| • | The ignition is ON. |
| • | Ignition voltage is greater than 9.5 volts. |
Conditions for Setting the DTC
| • | Steering angle sensor is reporting an internal electronic failure. |
| • | Steering angle sensor has not been initialized. |
| • | Steering angle sensor offset is greater than 15 degrees. |
Action Taken When the DTC Sets
| • | Vehicle stability enhancement system (VSES) are disabled. |
| • | The VSES indicator turns ON |
| • | The driver indicator turns ON |
Conditions for Clearing the DTC
| • | The condition for 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. |
Diagnostic Aids
| • | If DTC C0292 is set, diagnose that DTC first. |
| • | If the steering wheel position sensor is disconnected, DTCs will set and the EBCM will not provide 12-volt reference. |
| • | A poor ground connection for the EBCM may cause this DTC to set. |
Reference Information
Schematic Reference
Antilock Brake System Schematics
Connector End View Reference
Antilock Brake System Connector End Views
Description and Operation Reference
Electrical Information Reference
Scan Tool Reference
Scan Tool Data List for EBCM
Steering Angle Sensor Centering
Circuit/System Verification
- Position the steering wheel to the straight-ahead, centered, position.
- Install a scan tool, ignition ON, engine OFF, and view steering wheel position , the signal should be approximately 0° with the steering wheel straight ahead and should varies approximately 720+ or 720-.
- As the steering wheel is turned, signal should travel smoothly between 720°+ 720°-.
Circuit/System Testing
- Ignition OFF, disconnect the steering wheel position sensor (SWPS) connector.
- Ignition OFF, test for less than 1 ohm of resistance between the low reference circuit and ground.
- Test the CAN Hi circuit, CAN Lo circuit, 12-volt reference circuit, and the low reference circuit for an open/high resistance or a short to voltage or ground.
| ⇒ | If greater than 1 ohm, test the low reference circuit and the EBCM ground circuit for a short to voltage or an open/high resistance. If the circuits test normal, replace the EBCM. |
| ⇒ | If all circuits test normal, perform the steering positions calibration in EBCM, and Scan Tool Output Control. |
| ⇒ | If all circuits test normal, and the steering positions calibration failed, replace the SWPS. |
| ⇒ | If the DTC sets again after replacing the SWPS, replace the EBCM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for EBCM replacement, setup, and programming |
