GM Service Manual Online
For 1990-2009 cars only

Circuit Description

When the ignition switch is turned to ON, the sensing and diagnostic module (SDM) will perform a turn-on test to diagnose critical malfunctions within the SDM itself.

Upon passing this test, ignition and deployment loop voltages are measured to ensure they are within the normal voltage ranges. The SDM monitors the voltages at the driver low and the passenger low to detect shorts to ground or voltage in the deploy loops.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC 054 Left Side Air Bag Deployment Loop Short to Ground

Conditions for Running the DTC

Ignition voltage is within the normal operating voltage range.

Conditions for Setting the DTC

    • The side impact module wiring of the driver high is shorted to ground.
    • The side impact module wiring of the driver low is shorted to ground.

Action Taken When the DTC Sets

The SDM commands the AIR BAG indicator ON.

Conditions for Clearing the DTC

The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.

Step

Action

Values

Yes

No

Warning: Refer to Sensing and Diagnostic Module Voltage after Ignition is Turned Off Warning in the Preface section.

Warning: Refer to Sensing and Diagnostic Module Handling Warning in the Preface section.

Schematic Reference: SIR Schematics

Connector End View Reference: Component Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

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Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Confirm the ignition switch is OFF.
  2. Wait 1 minute for the sensing and diagnostic module (SDM) charger to be discharged.
  3. Visually inspect the air bag wiring for any damage.

Is there any visible damage to the air bag wiring?

--

Go to Step 4

Go to Step 3

3

Measure the resistance between the SDM and the high, low terminal of the driver side impact module and the ground.

Is the resistance equal to the specified value?

Go to Step 5

Go to Step 4

4

Replace the air bag wiring.

Did you complete the replacement?

--

Go to Step 7

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5

  1. Replace the SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement.
  2. Reconnect the negative battery cable.
  3. Use the scan tool in order to clear the DTCs.
  4. Perform the Diagnostic System Check - Vehicle.

Is DTC 054 still shown as a current fault?

--

Go to Step 6

Go to Step 7

6

Replace the driver side impact module.

Did you complete the replacement?

--

Go to Step 7

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7

  1. Reconnect all SIR components.
  2. Verify that all components, connectors and connector position assurances (CPAs) are properly mounted.
  3. Use the scan tool in order to clear the DTCs.
  4. Operate the vehicle within the Conditions for Running the DTC, as specified in the supporting text.

Does the DTC reset?

--

Go to Step 2

System OK