GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Suspension Controls Schematics

1

Did you review the system and circuit description and perform the necessary electrical and mechanical inspections?

Go to Step  2

Go to Symptoms - Air Suspension

2

Verify the fault is present.

Does the system operate normally?

Go to Testing for Electrical Intermittents in Wiring Systems

Go to Step  3

3

  1. Disconnect the air suspension dump valve.
  2. Ensure the air suspension dump switch is in the OFF position.
  3. Connect a test lamp between the control circuit of the air suspension dump valve and the ground circuit of the air suspension dump valve.
  4. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step  4

Go to Step  6

4

  1. Turn OFF the ignition.
  2. Disconnect the air suspension dump switch.
  3. Connect a test lamp between the control circuit of the air suspension dump valve and the ground circuit of the air suspension dump valve.
  4. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step  5

Go to Step  7

5

Test the air suspension dump valve control circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 8

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6

Replace the air suspension dump valve. Refer to Air Suspension Relief Valve Replacement .

Did you complete the replacement?

Go to Step 8

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7

Replace the air suspension dump switch.

Did you complete the replacement?

Go to Step 8

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8

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3