GM Service Manual Online
For 1990-2009 cars only

Circuit Description

With the ignition switch in the on position the current draw of both Air Suspension Sensors and the Air Suspension Pressure Sensor is verified by the Air Suspension Module to be within a calibrated range. If the current draw is out of range a DTC is set.

Conditions for Running the DTC

The ignition is on.

Conditions for Setting the DTC

The Air Suspension Module detects that the current drawn by the Air Suspension Sensors and Air Suspension Pressure Sensor is below 3 mA. or above 40 mA.

Action Taken When the DTC Sets

    • Air Suspension functionality is suspended.
    • SERVICE AIR SUSPENSION message is displayed.

Conditions for Clearing the DTC

DTC is cleared by cycling ignition.

Test Description

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

  1. Test Air Suspension Sensor current.

  2. Test the wiring for the overcurrent condition.

  3. Tests for the component that is creating the overcurrent.

Step

Action

Values

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, observe the Height Sensor Current parameter in the data list for the air suspension module.

Is the Height Sensor Current parameter within the specified range?

3-40 mA

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Disconnect the Air Suspension Sensor-LR, Air Suspension Sensor-RR and the Air Suspension Pressure Sensor.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the Height Sensor Current parameter.

Is the Height Sensor Current parameter less than the specified value?

40 mA

Go to Step 4

Go to Step 5

4

Reconnect the Air Suspension Sensors and Air Suspension Pressure Sensor one at a time while observing the Height Sensor Current parameter.

Is the Height Sensor Current parameter greater than the specified value when any of the components are reconnected?

40 mA

Go to Step 6

Go to Step 7

5

Test the 5 volt reference circuit of the Air suspension Sensors and Air Suspension Pressure Sensor for a short to ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 10

Go to Step 7

6

Inspect for poor connections at the harness connector of the Air Suspension Sensors and Air Suspension Pressure Sensor. Refer to Circuit Testing and to Wiring 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 Air Suspension Module. Refer to Testing for Intermittent Conditions and Poor Connections .

Did you find and correct the condition?

--

Go to Step 10

Go to Step 9

8

Replace the Air Suspension sensor or Pressure sensor. Refer to Air Spring Leveling Sensor Replacement or Air Spring Compressor Replacement .

Did you complete the replacement?

--

Go to Step 10

--

9

Important: Always perform the trim height check procedure after Air Suspension Module replacement.

  1. Replace the Air Suspension module. Refer to Air Spring Compressor Replacement .
  2. Recalibrate the trim height in the Air Suspension Module if necessary after 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.

Does the DTC reset?

--

Go to Step 2

System OK