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For 1990-2009 cars only

DTC C0545 Symptom 00

Circuit Description

The steering column shaft torque sensor is a 5-volt dual analog inverse signal device which is used to sense steering direction and the amount of torque being applied to the steering column shaft when the steering wheel is turned. The valid signal voltage range of the sensor is 0.25-4.75 volts. When applying torque to the steering column shaft during a right turn, the sensor's signal 1 voltage increases, while the signal 2 voltage decreases within the valid signal voltage range. When applying torque to the steering column shaft during a left turn, the sensor's signal 1 voltage decreases, while the signal 2 voltage increases within the valid signal voltage range.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0545 Steering Wheel Torque Input Sensor

This vehicle has DTCs which include DTC symptoms. For more information on DTC symptoms, refer to DTC Symptom Description .

DTC Symptom

DTC Symptom Descriptor

00

No Additional DTC Information

Condition for Running the DTC

    • The ignition is ON, with the engine ON.
    • Steering column shaft torque input is present.

Condition for Setting the DTC

    • The torque sensor's signal 1/signal 2 voltages are less than 0.25 volt, or greater than 4.75 volts.
    • A short to ground, short to voltage, or an open in the torque sensor, or the circuits to the sensor

Action Taken When the DTC Sets

    • DTC C0545 00 is stored in memory.
    • The DIC displays the POWER STEERING warning message.
    • No steering assist is provided.

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.
    • Using a scan tool

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. Tests if the sensor is within the valid signal voltage range.

  2. The use of EL-47564 power steering control module (PSCM) test harness in steps 3-5 tests if the malfunction is internal to the PSCM.

  3. Tests if the low reference circuit is opened or shorted internal to the PSCM. Since the torque sensor's signal 1 and signal 2 data parameters both drop to 0.0 V when the torque/position sensor connector is disconnected, the position sensor's signal 1 data parameter is used to verify low reference circuit operation.

  4. Tests if the torque/position sensor harness is damaged. Since both ends of the harness cannot be accessed, only visual circuit inspection can be performed.

Step

Action

Value(s)

Yes

No

Schematic Reference: Power Steering Schematics

Connector End View Reference: Power Steering Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, observe the Torque Sensor Signal 1 and the Torque Sensor Signal 2 Data parameters in Data Display.

Does the scan tool indicate the Torque Sensor Signal 1 and Signal 2 Data parameters are within the specified range?

0.25-4.75 V

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Disconnect the torque/position sensor harness connector from the power steering control module (PSCM).
  3. Connect the EL-47564 PSCM test harness.
  4. Connect a 3-amp fused jumper wire between the 5-volt reference circuit and the steering shaft torque signal 1 circuit of the PSCM test harness connector end.
  5. Turn ON the ignition, with the engine OFF.
  6. With the scan tool, observe the Torque Sensor Signal 1 data parameter.

Does the scan tool indicate the Torque Sensor Signal 1 data parameter is less than the specified value?

4.9-5 V

Go to Step 8

Go to Step 4

4

  1. Connect a 3-amp fused jumper wire between the 5-volt reference circuit and the steering shaft torque signal 2 circuit of the PSCM test harness connector end.
  2. With the scan tool, observe the Torque Sensor Signal 2 data parameter.

Does the scan tool indicate the Torque Sensor Signal 2 data parameter is less than the specified value?

4.9-5 V

Go to Step 8

Go to Step 5

5

  1. Connect a 3-amp fused jumper wire between the low reference circuit and the steering position sensor signal 1 circuit of the PSCM test harness connector end.
  2. With the scan tool, observe the Steering Position Sensor Signal 1 data parameter.

Does the scan tool indicate the Steering Position Sensor Signal 1 data parameter is greater than the specified value?

0.0 V

Go to Step 8

Go to Step 6

6

  1. Turn OFF the ignition.
  2. Inspect for poor connections at the torque/position sensor harness connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 10

Go to Step 7

7

Visually inspect the torque/position sensor harness for any damaged wires. Refer to Wiring Repairs and Repairing Damaged Wire Insulation .

Did you find and correct the condition?

--

Go to Step 10

Go to Step 9

8

Replace the power steering motor/module assembly. Refer to Power Steering Assist Motor Replacement .

Did you complete the replacement?

--

Go to Step 10

--

9

Replace the torque sensor. Refer to Steering Column Replacement .

Did you complete the replacement?

--

Go to Step 10

--

10

  1. Use the scan tool in order to clear the DTC.
  2. Operate the vehicle within the conditions for running the DTC.

Does the DTC reset?

--

Go to Step 2

System OK

DTC C0545 Symptom 4B

Circuit Description

After replacing the power steering control module (PSCM), the steering shaft torque sensors center position must be calibrated.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0545 Steering Wheel Torque Input Sensor

This vehicle has DTCs which include DTC symptoms. For more information on DTC symptoms, refer to DTC Symptom Description in Vehicle DTC Information.

Symptom Type

Symptom Type Descriptor

4B

Calibration not Learned

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The PSCM has not undergone the torque sensor calibration procedure.

Action Taken When the DTC Sets

    • DTC C0545 4B is stored in memory.
    • The DIC displays the POWER STEERING warning message.
    • Slight steering effort imbalance.

Conditions for Clearing the DTC

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

Diagnostic Aids

DTC  C0545 4B will set upon the first ignition ON cycle after PSCM replacement.

Step

Action

Yes

No

1

Did you perform the Vehicle Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, monitor the DTC Information for DTC C0545 4B.

Does the scan tool indicate that DTC C0545 4B is current?

Go to Step 3

Go to Step 4

3

Calibrate the torque sensor. Refer to Control Module Setup .

Did you complete the repair?

Go to Step 4

--

4

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the conditions for running the DTC.

Does the DTC reset?

Go to Step 2

System OK