GM Service Manual Online
For 1990-2009 cars only

The Air Suspension system has an internal clock to prevent overheating if the compressor assembly is running for a prolonged period of time. If the system overheats, all leveling function stops until the system cools down. During this time, the indicator LED on the air inflator switch will be quickly flashing at a constant rate.

The other three diagnostic trouble codes are displayed with a blink code on the inflator switch LED. The Air Suspension Compressor Assembly shall begin to indicate the code when the condition to cause the code becomes current.

The number of the fault code shall be represented by the number of flashing pulses on the inflator switch LED. The flashing pulses shall have a repetition rate of 0.5 seconds and each code shall be separated by a 3.0 second delay. All codes shall be flashed in the order of occurrence of the fault. The blink code shall take priority over other processes that have access to the inflator switch LED. Refer to the following:

    •  DTC 001
    •  DTC 002
    •  DTC 003