GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The air suspension compressor assembly monitors the calibrations in the electrically erasable programmable read-only memory (EEPROM). The module also monitors the compressor, solenoids and internal wiring for faults.

Conditions for Running the DTC

The ignition is on.

Conditions for Setting the DTC

The air suspension compressor assembly detects an invalid EPROM checksum or internal component failure.

Action Taken When the DTC Sets

Depending on the condition that set the DTC, some or all functions will be disabled.

Conditions for Clearing the DTC

The DTC will automatically clear when the condition for setting the DTC is removed and the ignition has cycled from on to off to on.

Diagnostic Aids

The air suspension compressor assembly will set a DTC 001 when any of these conditions are present:

    • A checksum error in EEPROM is present.
    • The compressor is shorted or open.
    • The compressor solenoids are shorted or open.

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

Verify the fault is present.

Does the system operate normally?

Go to Testing for Intermittent Conditions and Poor Connections in wiring systems.

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Turn ON the ignition, with the engine OFF.

Does the LED flash DTC 001?

Go to Step 4

Go to Step 5

4

Replace the air suspension compressor assembly.

Refer to Automatic Level Control Air Compressor Replacement

Did you complete the replacement?

Go to Step 5

--

5

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Diagnostic System Check - Air Suspension