GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The Air Suspension Module monitors the trim height calibration procedure. When the calibration procedure is activated the vehicle exhaust down to rest on a chassis support at a predetermined height. When no further height change is detected, the height sensor readings are verified to be within 2.06 V and 2.88 V. If there are no errors then the new trim height is accepted. If the Air Suspension Module detects any errors in the trim height calibration procedure then the new trim height is not accepted and a DTC is set.

Conditions for Running the DTC

Ignition on

Conditions for Setting the DTC

The Air Suspension Module detects that the height sensors are not within 2.06 V and 2.88 V.

Action Taken When the DTC Sets

The new trim height is not accepted.

Conditions for Clearing the DTC

The DTC will clear when the condition for setting the DTC is removed

Diagnostic Aids

Make sure the vehicle chassis is being supported at the proper trim height.

Test Description

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

  1. Tests whether the condition is module, system, or condition related.

  2. Tests if the condition has been corrected or identified as specified in the supporting text.

  3. Test if the Air Suspension Sensors are within the proper range before the relearn procedure is activated.

Step

Action

Yes

No

Schematic Reference: Suspension Controls Schematics

1

Did you perform the Air Suspension Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Air Suspension

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 C0569 in the Air Suspension Module.

Does the scan tool indicate that DTC C0569 is current?

Go to Step 4

Go to Step 3

3

Most occurrences of this DTC are caused by not having the vehicle supported at the proper trim height when doing the trim height relearn procedure.

Did trim height relearn procedure cause this DTC to set?

Go to Diagnostic Aids

Go to Step 4

4

  1. Use the scan tool in order to clear the DTCs.
  2. Activate the trim height relearn procedure after making sure the vehicle is being supported at the correct trim height.

Does the DTC reset?

Go to Step 5

System OK

5

If needed, inspect the Right and Left Height Sensor voltage reading with the scan tool to be sure that they read between 2.06 V and 2.88 V after the Air Suspension system has exhausted.

Did you find and correct the condition ?

System OK

Go to Step 6

6

Important: Always check the trim height and recalibrate the Air Suspension module if necessary.

  1. Replace the Air Suspension Module. Refer to Air Spring Compressor Replacement .
  2. Check the trim height and recalibrate the Air Suspension Module if necessary.

Did you complete the replacement?

System OK

--