GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The torque sensor converts the rotation torque input from the steering wheel into electric signals and sends them to the power steering control module.

DTC Descriptor

This diagnostic procedure supports the following DTC:

    • DTC C1511 Torque Sensor Circuit Malfunction
    • DTC C1512 Torque Sensor Circuit Malfunction
    • DTC C1513 Torque Sensor Circuit Malfunction
    • DTC C1514 Torque Sensor Power Supply Abnormal
    • DTC C1515 Torque Hold Abnormal

Conditions for Running the DTC

This DTC shall run when key is inserted into key cylinder.

Conditions for Setting the DTC

The power steering control module has detected a torque sensor malfunction.

Action Taken When the DTC Sets

    • Power assist stops.
    • The P/S warning indicator illuminates.

Conditions for Clearing the DTC

The DTC will clear when conditions for setting the DTC have been repaired.

Diagnostic Aids

If the steering column or power steering control module has been replaced, the rotation angle sensor initialization and torque sensor zero point calibration, must be performed. Refer to Steering Angle Sensor Initialization and Steering Shaft Torque Sensor Zero Point Calibration .

Step

Action

Value(s)

Yes

No

Schematic Reference: Power Steering Schematics

Connector End View Reference: Component Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

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Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Inspect the connections between the torque sensor and the power steering control module.

Is the torque sensor connection to the control module secure?

 

Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections

3

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With the scan tool, observe the Torque Sensor 1 and Torque Sensor 2 parameters in the data list.
  4. Check for the torque sensor output voltages as follows:
  5. • Torque sensor 1 with steering wheel not turned
    • Torque sensor 1 with steering wheel turned to the right
    • Torque sensor 1 with steering wheel turned to the left
    • Torque sensor 2 with steering wheel not turned
    • Torque sensor 2 with steering wheel turned to the right
    • Torque sensor 2 with steering wheel turned to the left

Is the voltage measured less than or greater than the specified values?

Torque Sensor 1 not turned = 2.3 V - 2.7 V

Torque Sensor 1 turned right = 2.5 V - 3.8 V

Torque Sensor 1 turned left = 1.2 V - 2.5 V

Torque Sensor 2 not turned = 2.3 V - 2.7 V

Torque Sensor 2 turned right = 1.2 V - 2.5 V

Torque Sensor 2 turned left = 2.5 V - 3.8 V

Go to Step 4

Go to Step 6

4

  1. Turn the ignition ON, with the engine OFF.
  2. Measure the voltage between Connector A1 terminals 6 and 8.

Is the voltage measured within the specified value?

4.5 V - 5.5 V

Go to Step 5

Go to Step 6

5

  1. Turn the ignition ON, with the engine OFF.
  2. Measure the voltages as follows:
  3. • At connector A1 terminals 5 and 8 with steering wheel not turned
    • At connector A1 terminals 5 and 8 with steering wheel turned right
    • At connector A1 terminals 5 and 8 with steering wheel turned left
    • At connector A1 terminals 7 and 8 with steering wheel not turned
    • At connector A1 terminals 7 and 8 with steering wheel turned right
    • At connector A1 terminals 7 and 8 with steering wheel turned left

Is the voltage measured less than or greater than the specified values?

Not turned = 2.3 V - 2.7 V

Turned right = 2.5 V - 3.8 V

Turned left = 1.2 V - 2.5 V

Not turned = 2.3 V - 2.7 V

Turned right = 1.2 V - 2.5 V

Turned left = 2.5 V - 3.8 V

Go to Step 6

Go to Step 7

6

Replace the power steering control module. Refer to Control Module References for power steering control module replacement, setup and programming.

Did you complete the replacement?

1 Ohm

Go to Step 8

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7

Replace the steering column. Refer to Steering Column Replacement .

Did you complete the replacement?

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Go to Step 8

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8

  1. Use the scan tool in order to clear the DTC.
  2. Operate the vehicle within the Conditions for Running the DTC, as specified in the supporting text.

Does the DTC reset?

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Go to Step 2

System OK