GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Engine Exhaust Brake Schematics

1

Did you review the Exaust Brake Description and Operation and perform the necessary inspections?

Go to Step 2

Go to Symptoms - Engine Exhaust Brake

2

Turn OFF the ignition.

Does the auxiliary air compressor turn OFF?

Go to Step 5

Go to Step 3

3

Disconnect the auxiliary air tank switch connector.

Does the auxiliary air compressor turn OFF?

Go to Step 4

Go to Step 6

4

Repair the short to voltage in the ignition 3 circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 9

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5

Inspect the auxiliary air compressor system and accessories for a leak.

Did you find and correct the condition?

Go to Step 9

Go to Step 8

6

  1. Disconnect the auxiliary air compressor relay.
  2. Test for a short to voltage in the battery positive voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 7

7

Replace the auxiliary air compressor relay.

Did you complete the replacement?

Go to Step 9

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8

Replace the auxiliary air tank pressure switch.

Did you complete the replacement?

Go to Step 9

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9

  1. Turn ON the ignition.
  2. Wait up to 5 minutes.

Does the auxiliary air system pressurize then turn off.

System OK

Go to Step 2