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 Descriptor

DTC C0545 00: Steering Wheel Torque Input Sensor

Diagnostic Fault Information

Circuit

Short to Ground

Open or High Resistance

Short to Voltage

Signal Performance

torque sensor

C0545 00*

C0545 00*

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--

*After verifying a circuit fault exists in the power steering wiring harness extension harness for two mode hybrid. The wiring harness is to be replaced and not repaired

Circuit/System Description

The power steering control module (PSCM) continuously monitors the torque sensor input and output shaft sine wave frequency signals. As the steering wheel is turned and torsional twist is applied to the steering column shaft, the torque sensors input and output shaft sine wave frequency signals are processed by the PSCM to detect and calculate the steering torque.

Conditions for Running the DTC

Ignition ON.

Conditions for Setting the DTC

    • The PSCM detects open, short to ground or short between any of the torque sensor circuits.
    • The PSCM detects the steering torque is outside the valid range of -7 to +7 N·m.

Actions Taken When DTC Sets

    • DTC C0545 is stored in memory.
    • The driver information center (DIC) displays the SERVICE POWER STEERING warning message.
    • No steering assist.

Conditions for Clearing the DTC

    • A current DTC will clear on the next malfunction free ignition cycle.
    • A history DTC will clear after 100 consecutive malfunction free ignition cycles.

Reference Information

Schematic Reference

Power Steering Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Power Steering System Description and Operation

Electrical Information Reference

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

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

Danger: Always perform the High Voltage Disabling procedure prior to servicing any High Voltage component or connection. Personal Protection Equipment (PPE) and proper procedures must be followed.

The High Voltage Disabling procedure will perform the following tasks:

   • Identify how to disable high voltage.
   • Identify how to test for the presence of high voltage.
   • Identify condition under which high voltage is always present and personal protection equipment (PPE) and proper procedures must be followed.
Failure to follow the procedures exactly as written may result in serious injury or death.

Important: After verifying a circuit fault exists in the Power Steering Wiring Harness Extension Harness for Two Mode Hybrid. The wiring harness is to be replaced and not repaired.

  1. Perform the High Voltage Disabling procedure.
  2. Ignition OFF, connect the 12-volt battery.
  3. Ignition OFF, disconnect the X3 harness connector at the PSCM.
  4. Test for 2-20 Ω between the signal circuit terminal 4 and the low reference circuit terminal 6.
  5. If not within the specified range, test the circuits for a short to ground, an open/high resistance, or a short together. If the circuits test normal, replace the power steering gear.
  6. Test for 100-500 Ω between the signal circuit terminal 10 and the low reference circuit terminal 9.
  7. If not within the specified range, test the circuits for an open/high resistance, or a short together. If the circuits test normal, replace the power steering gear.
  8. Test for 300-1000 Ω between the signal circuit terminal 11 and the low reference circuit terminal 9.
  9. If not within the specified range, test the appropriate circuit for an open/high resistance, or a short together. If the circuits test normal, replace the power steering gear.
  10. Test for 50-200 Ω between the signal circuit terminal 12 and the low reference circuit terminal 9.
  11. If not within the specified range, test the circuits for an open/high resistance, or a short together. If the circuits test normal, replace the power steering gear.
  12. Test for 200-800 Ω between the signal circuit terminal 13 and the low reference circuit terminal 9.
  13. If not within the specified range, test the circuits for an open/high resistance, or a short together. If the circuits test normal, replace the power steering gear.
  14. Test for infinite resistance between the low reference terminal 6 and low reference terminal 9.
  15. If less than the specified value, test the circuits for a short together. If the circuits test normal, replace the power steering gear.
  16. Test for greater than infinite resistance between the following circuits listed below and the EPS motor housing.
  17. • Low reference terminal 9
    • Low reference terminal 6
    If less than the specified range, test the appropriate circuit for a short to ground. If the circuits test normal, replace the power steering gear.
  18. If all circuits test normal, test or replace the PSCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Power Steering Wiring Harness Extension Harness Replacement
    •  Steering Gear Replacement
    •  Control Module References for PSCM replacement, setup, and programming