GM Service Manual Online
For 1990-2009 cars only

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 00 : 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 5-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 5-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.

The steering angle sensor provides a serial data 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 5-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

ABS Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Scan Tool Data List for EBCM

Circuit/System Verification

  1. Position the steering wheel to the straight-ahead, centered, position.
  2. Install a scan tool, ignition ON, engine OFF, and view SWPS signal A and SWPS signal B. One of the signals should be approximately 2.5 volts and the other should be approximately 0 volts.
  3. As the steering wheel is turned, each signal should travel smoothly between 0 and 5 volts.

Circuit/System Testing

  1. Ignition OFF, disconnect the steering wheel position sensor (SWPS) connector.
  2. Ignition OFF, test for less than 1 ohm of resistance between the low reference circuit and ground.
  3. 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.
  4. Test the CAN Hi circuit, CAN Lo circuit, 5-volt reference circuit, and the low reference circuit for an open/high resistance or a short to voltage or ground.
  5. If all circuits test normal, 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.

    •  Steering Angle Sensor Centering
    •  Diagnostic Test Drive
    •  Control Module References for EBCM replacement, setup, and programming