GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The speed sensitive power steering (SSPS) control module uses the steering wheel position sensor to determine the angle speed of the steering wheel. If the angle speed were big enough for intervention into normal steering force control during high vehicle speed, which means a driver made an evasive steering maneuver to avoid an accident, SSPS module would supply enough steering support. The steering wheel position sensor is a potentiometer type sensor with the following 3 circuits:

    • A 5-volt reference
    • A low reference
    • A signal

Conditions for Running the DTC

    • The ignition is ON.
    • Turn the steering wheel 180 degrees.

Conditions for Setting the DTC

    • Open circuit or short to ground on the steering wheel position sensor signal circuit
    • Open circuit or short to ground on the steering wheel position sensor 5-volt reference signal
    • A defective steering wheel position sensor

Action Taken When the DTC Sets

    • The SSPS warning light will illuminate.
    • Power steering assist will default to full power steering effort.
    • The SSPS will store a DTC 06 in memory.

Conditions for Clearing the DTC

    • Conditions for the fault are no longer present.
    • Use the scan tool in order to clear the DTC and cycle the ignition in order to clear the warning lamp.

Diagnostic Aids

Check for the following conditions if a history or intermittent DTC is indicated.

    • A poor connection at the SSPS control module. Inspect the harness connectors for backed out terminals, improper mating, improperly formed or damaged terminals, and poor terminal to wire connections.
    • A damaged wiring harness. Inspect the wiring harness for damages. If the wiring harness appears to be in good condition, observe the display on the DMM while moving the connectors and wiring harnesses related to the actuator. A change in the DMM display during the test will indicate the location of the fault.
    • For additional information, refer to Testing for Intermittent Conditions and Poor Connections .

Test Description

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

  1. This test checks for an open circuit or short to ground in the steering wheel position sensor circuits.

  2. This test checks for an open circuit or short to ground on the 5-volt reference circuit

  3. This test checks for a poor connection at the SSPS control module.

  4. This test checks for short to ground in the high actuator control circuits of the SSPS control module.

  5. This test checks for a poor connection at the power steering fluid flow control valve actuator.

Step

Action

Values

Yes

No

Schematic Reference: Steering Assist Schematics

Connector End View Reference: Steering Assist 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

  1. Disconnect the steering wheel position sensor.
  2. Turn ON the ignition with the engine OFF.
  3. Use a DMM to measure the voltage between the 5-volt reference circuit and the low reference circuit to the steering wheel position sensor. Refer to Circuit Testing .

Is the measured resistance within the specified value?

4.8-5.2 V

Go to Step 5

Go to Step 3

3

Test for an open or short to ground in the steering wheel position sensor 5-volt reference circuit. Refer to Testing for Continuity and Wiring Repairs .

Did you find and correct the condition?

 

Go to Step 9

Go to Step 4

4

Test for a poor connection at the speed sensitive power steering (SSPS) control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 9

Go to Step 7

5

Test for an open or short to ground in the steering wheel position sensor signal circuit. Refer to Testing for Continuity and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 9

Go to Step 6

6

Test for a poor connection at the steering wheel position sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 9

Go to Step 8

7

Replace the power steering control module. Refer to Power Steering Control Module Replacement .

Is the repair complete?

--

Go to Step 9

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8

Replace the steering wheel position sensor. Refer to Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement .

Is the repair complete?

--

Go to Step 9

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9

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2