GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2001 🢒 Express 🢒 Body and Accessories 🢒 Instrument Panel, Gauges, and Console 🢒 Air Bag Indicator Does Not Come ON

Circuit Description

The AIR BAG indicator is controlled by the inflatable restraint sensing and diagnostic module (SDM). When the ignition is turned ON, the SDM performs tests to diagnose critical malfunctions within itself. The SDM then commands the AIR BAG indicator OFF after it has flashed seven times. If a malfunction is detected, the AIR BAG indicator will be turned ON solid.

Diagnostic Aids

A broken or chafed wire in the AIR BAG indicator control circuit may cause an intermittent condition to occur. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Test Description

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

  1. Tests for an open or high resistance in the AIR BAG indicator control circuit.

    2.

  2. Inspects for poor connections at the SDM harness connector.

    3.

  3. Inspects for poor connections at the instrument panel cluster (IPC) harness connector.

Air Bag Warning Lamp Does Not Come On

Step

Action

Yes

No

Schematic Reference: SIR Schematics

1

Did you perform the Diagnostic System Check - SIR?

Go to Step 2

Go to Diagnostic System Check - SIR

2
  1. Turn OFF the ignition.
  2. Observe the AIR BAG indicator while turning the ignition ON, with the engine OFF.

Does the AIR BAG indicator turn ON?

Go to Diagnostic Aids

Go to Step 3

3
  1. Turn OFF the ignition.
  2. Disable the SIR system. Refer to Disabling the SIR System .
  3. Disconnect the SDM connector. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement .
  4. Connect a 3 amp fused jumper wire between the AIR BAG indicator control circuit and a known good ground.
  5. Turn ON the ignition, with the engine OFF.

Does the AIR BAG indicator remain OFF?

Go to Step 4

Go to Step 5

4

  1. Turn OFF the ignition.
  2. Test the AIR BAG indicator control circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 6

5

  1. Turn OFF the ignition.
  2. Disconnect the fused jumper wire.
  3. Inspect the SDM connector for corrosion or damage. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 7

6

Inspect the IPC connector for corrosion or damage. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 8

7

Replace the SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement .

Did you complete the replacement?

Go to Step 9

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8

Repair or replace the IPC. Refer to Instrument Cluster Replacement in Instrument Panel, Gauges and Console.

Did you complete the repair?

Go to Step 9

--

9
  1. Reconnect all SIR system components.
  2. Verify that all components, connectors and CPAs are properly mounted.

Have all SIR and IPC components been reconnected and properly mounted?

Go to Diagnostic System Check - SIR

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