GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The suspension damper solenoid is driven ON and OFF by the electronic suspension control (ESC) module. To activate the suspension damper solenoid, it is initially subjected to full battery voltage for a short period of time. Once the suspension damper solenoid is pulled in, the supply voltage is pulse width modulated (PWM). The amount the suspension damper solenoid valve activated is based on inputs from the driver tow/haul switch, road inputs, position sensor inputs, and the powertrain control module (PCM).

DTC Descriptors

This diagnostic procedure supports the following DTCs:

    • DTC C0575 Left Front Solenoid Circuit
    • DTC C0580 Right Front Solenoid Circuit
    • DTC C0585 Left Rear Solenoid Circuit
    • DTC C0590 Right Rear Solenoid Circuit

Conditions for Running the DTC

The ESC module performs a test on each suspension damper solenoid during both the ON and OFF states.

Conditions for Setting the DTC

    • A short to ground in the control circuit of the suspension damper solenoid
    • A short to voltage in the control circuit of the suspension damper solenoid
    • An open in the control circuit of the suspension damper solenoid
    • An open in the solenoid low reference circuit of the suspension damper solenoid
    • A short to voltage in the solenoid low reference circuit of the suspension damper solenoid

Action Taken When the DTC Sets

    • The suspension damper solenoid will be disabled.
    • All suspension damper solenoids will be disabled.
    • The SERVICE RIDE CONTROL message will be displayed.
    • Stores a DTC C0575, C0580, C0585, or C0590 in the ESC module memory

Conditions for Clearing the DTC

    • The ESC module no longer detects a problem in the low reference circuit or the control circuit of the suspension damper solenoid.
    • Using the scan tool
    • A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.

Diagnostic Aids

Important: Ignition cycle counting is used by the ESC module to detect faults in the system. The objective is to eliminate false/intermittent codes while maintaining an acceptable level of system performance. The operation of the ignition cycle counting requires that a fault condition be present for 4 consecutive ignition cycles before it will set the fault code and display the SERVICE RIDE CONTROL message. If a fault code is present, without a fault being current, the system will go into one or more degraded modes without displaying a message. Resetting the ignition cycle counter is done by clearing codes with a scan tool. Clearing codes will override ignition cycle counting for one ignition cycle. Therefore, a fault condition will set the fault code immediately if it occurs on the first ignition cycle after the codes are cleared.

If DTC C0870 or C0690 is present, repair the malfunction for these DTCs before diagnosing DTC C0575, C0580, C0585, or C0590.

It may be necessary to check Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Test Description

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

  1. This step tests for low reference circuit of the suspension damper solenoid. The ESC module supplies ground of the suspension damper solenoid.

  2. This step verifies that the resistance of the suspension damper solenoid.

  3. This step tests the control circuit to the suspension damper solenoid for an open and short to voltage.

  4. This step tests the control circuit for a short to ground.

  5. Replace and program the ESC module.

Step

Action

Value(s)

Yes

No

Schematic Reference: Suspension Controls Schematics

1

Did you perform the Diagnostic System Check - Vehicle?

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Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Turn ON the ignition, with the engine OFF.
  2. Probe the low reference circuit of the suspension damper solenoid with a test lamp that is connected to a positive battery voltage circuit. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

--

Go to Step 3

Go to Step 8

3

  1. Turn OFF ignition.
  2. Disconnect the suspension damper solenoid connector at the shock absorber.
  3. Measure the resistance from the control circuit of the suspension damper solenoid to the low reference circuit of the suspension damper solenoid on the shock absorber.

Does the resistance of the shock absorber measure within the specified value?

1.5-3.3 ohms

Go to Step 4

Go to Step 6

4

Test the control circuit of the suspension damper solenoid for a short to voltage and an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 5

5

Test the control circuit of the suspension damper solenoid 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 11

Go to Step 7

6

Inspect for poor connections at the suspension damper solenoid. 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

7

Inspect for poor connections at the harness connector of the electronic suspension control (ESC) 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 11

Go to Step 10

8

Test the low reference circuit of the suspension damper solenoid for an open and short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 10

9

Replace the shock absorber. Refer to Shock Absorber Replacement in Front Suspension or Shock Absorber Replacement in Rear Suspension.

Did you complete the replacement?

--

Go to Step 11

--

10

Replace the ESC module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

--

Go to Step 11

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11

  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