GM Service Manual Online
For 1990-2009 cars only

Object Number: 582074  Size: MF
Suspension Controls Component Views
Power and Ground
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice
Road Sensing Suspension Control Module Description
Antilock Brake System Connector End Views

Circuit Description

The Electronic Suspension Control (ELC) module receives a Pulse-Width Modulation (PWM) steering position signal from the Electronic Brake Control Module (EBCM). The Electronic Suspension Control (ELC) module monitors the PWM steering position circuit to determine if a valid signal is sent from the EBCM.

Conditions for Running the DTC

    • The Ignition is on.
    • The fault is detected during three consecutive ignition cycles, or during the same ignition cycle after clearing the DTC with a scan tool.

Conditions for Setting the DTC

The Electronic Suspension Control (ELC) module does not detect a valid steering position signal from the EBCM for 5.0 seconds.

Action Taken When the DTC Sets

    • The Electronic Suspension Control (ELC) module ignores the steering position signal input.
    • The Electronic Suspension Control (ELC) module continues to control the shock absorbers using the lateral acceleration data sent from the EBCM on the serial data line.
    • The SERVICE RIDE CONTROL message will be displayed.

Conditions for Clearing the MIL/DTC

    • The scan tool can be used to clear the DTC.
    • The On-Board diagnostic CLEAR RSS CODES feature can be used to clear the DTC.
    • The DTC is saved as history when the Electronic Suspension Control (ELC) module detects a valid steering position signal from the EBCM. The DTC will clear if the fault does not return after 50 consecutive ignition cycles.

Diagnostic Aids

    • The following conditions may cause an intermittent malfunction:
      • An intermittent open circuit condition on the steering position sensor circuit.
      • A short to ground or to voltage in the steering position sensor circuit.
      • Intermittent operation of the EBCM.
    • If the Electronic Suspension Control (ELC) module does not receive a valid steering position signal from the EBCM, the CVRSS system will still function, but will ignore the steering position signal. The CVRSS system uses lateral acceleration data sent from the EBCM on the serial data line in order to substitute for a loss of the steering position signal.
    • An intermittent open circuit condition, or a short circuit condition to ground or voltage on the steering position sensor circuit may cause a random firm/soft ride condition.
    • If the DTC is a history DTC, the problem may be intermittent. Using a scan tool, monitor the steering position sensor circuit while moving the related wiring and connectors. This can often cause the malfunction to appear.

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. This step tests for normal function of the EBCM.

  2. This step tests for normal function of the EBCM

  3. This step tests for an intermittent or poor connection at the EBCM.

  4. This step tests for a short to ground in the Steering Wheel Position Signal circuit.

Step

Action

Value(s)

Yes

No

1

Did you perform the Road Sensing Suspension Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, observe the Steering Position PWM parameter in the Electronic Suspension Control (ELC) module data list.

Does the scan tool indicate that the Steering Position PWM Parameter is within the specified range?

0-10 ms.

Go to Step 3

Go to Step 4

3

  1. Activate the Steering Position PWM input.
  2. With the scan tool, observe the Steering Position PWM data parameter while turning the steering wheel.

Does the Steering Position PWM data parameter change state while the steering wheel is turned?

--

Go to Diagnostic Aids

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Disconnect the EBCM.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the Steering Position PWM data parameter.

Does the scan tool indicate that the Steering Position PWM Parameter is within the specified range?

0-10 ms.

Go to Step 7

Go to Step 5

5

Test the signal circuit of the EBCM for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 10

Go to Step 6

6

Inspect for poor connections at the harness connector of the Electronic Suspension Control (ELC) module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 10

Go to Step 8

7

Inspect for poor connections at the harness connector of the EBCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 10

Go to Step 9

8

Important: Perform the set up procedure for the Electronic Suspension Control (ELC) module.

Replace the Electronic Suspension Control (ELC) module. Refer to Electronic Suspension Control Module Replacement .

Did you complete the replacement?

--

Go to Step 10

--

9

Replace the EBCM. Refer to Electronic Brake Control Module Replacement .

Did you complete the replacement?

--

Go to Step 10

--

10

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

Does the DTC reset?

--

Go to Step 2

System OK