For 1990-2009 cars

### 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 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 Angle Sensor Signal | C0460 39 | C0460 39 | -- | --
Low Reference | C0460 39 | C0460 39 | -- | --
Steering Wheel Position Signal Can HI | C0460 39 | C0460 39 | -- | C0460 42, 4B, 5A, 71, 72
Steering Wheel Position Signal Can Lo | C0460 39 | C0460 39 | -- | C0460 42, 4B, 5A, 71, 72

### Circuit/System Description

The electronic brake control module (EBCM) supplies ignition voltage to the steering angle sensor and the yaw-rate/lateral sensor. The EBCM receives serial data messages from both the steering angle sensor and the yaw rate/lat sensor.

The steering angle sensor serial data message to the EBCM represents the steering wheel degree of rotation. The EBCM utilizes this signal to calculate the driver intended driving direction.

### Conditions for Running the DTC

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.

• | The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

### Diagnostic Aids

• | If the steering wheel position sensor is disconnected, DTCs will set and the EBCM will not provide voltage to the sensor.

• | A poor ground connection for the EBCM may cause this DTC to set.

• | Improperly mounted or loose steering angle sensor.

### Reference Information

#### Schematic Reference

Antilock Brake System Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation Reference

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

1. Position the steering wheel to the straight-ahead, centered, position.
2. Ignition ON, engine OFF, observe the scan tool Steering Wheel Position parameter, the signal should be approximately 0° with the steering wheel straight ahead, and turning the steering wheel the signal should travel smoothly between +720° -720°

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the steering wheel position sensor (SWPS).
2. Test for less than 1 ohm between the low reference circuit terminal 6 and ground.

⇒ | If greater than specified range, test the low reference circuit for an open/high resistance. If the circuits test normal, replace the EBCM.

3. Disconnect the harness connector at the EBCM.
4. Ignition ON, test for 0 volts between the communication circuit terminal 19 and ground at the EBCM connector.

⇒ | If greater than the specified value, repair the communication circuit for a short to voltage.

5. Test for 0 volts between the communication circuit terminal 18 and ground.

⇒ | If greater than the specified value, repair the communication circuit for a short to voltage.

6. Ignition OFF, test for infinite resistance between the communication circuit terminal 19 and ground.

⇒ | If greater than the specified value, repair the communication circuit for a short to ground.

7. Ignition OFF, test for infinite resistance between the communication circuit terminal 18 and ground.

⇒ | If greater than the specified value, repair the communication circuit for a short to ground.

8. Test for less than 1 ohm between the communication circuit terminals 19 and terminal 4.

⇒ | If greater than the specified range, repair the communication circuit for an open/high resistance.

9. Test for less than 1 ohm between the communication circuit terminals 18 and terminal 3.

⇒ | If greater than the specified range, repair the communication circuit for an open/high resistance.

10. Test for infinite resistance between the communication circuit 18 and the communication circuit 19.

⇒ | If not the specified value, test the communication circuits for a short together.

11. If all circuits test normal, replace the steering angle sensor.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Steering Wheel Position Sensor Replacement

• | Control Module References for EBCM replacement, setup, and programming