GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC B0019 01 : Passenger Frontal Deployment Loop Stage 1 Short to Battery

DTC B0019 02 : Passenger Frontal Deployment Loop Stage 1 Short to Ground

DTC B0019 04 : Passenger Frontal Deployment Loop Stage 1 Open Circuit

DTC B0019 0D : Passenger Frontal Deployment Loop Stage 1 Resistance Above Threshold

DTC B0019 0E : Passenger Frontal Deployment Loop Stage 1 Resistance Below Threshold

DTC B0020 01 : Passenger Frontal Deployment Loop Stage 2 Short to Battery

DTC B0020 02 : Passenger Frontal Deployment Loop Stage 2 Short to Ground

DTC B0020 04 : Passenger Frontal Deployment Loop Stage 2 Open Circuit

DTC B0020 0D : Passenger Frontal Deployment Loop Stage 2 Resistance Above Threshold

DTC B0020 0E : Passenger Frontal Deployment Loop Stage 2 Resistance Below Threshold

Diagnostic Fault Information

Circuit

Short to Ground

High Resistance

Open

Short to Voltage

Signal Performance

I/P Module Stage 1 High Circuit

B0019 02

B0019 0D

B0019 04

B0019 01

B0019 0E

I/P Module Stage 1 Low Circuit

B0019 02

B0019 0D

B0019 04

B0019 01

B0019 0E

I/P Module Stage 2 High Circuit

B0020 02

B0020 0D

B0020 04

B0020 01

B0020 0E

I/P Module Stage 2 Low Circuit

B0020 02

B0020 0D

B0020 04

B0020 01

B0020 0E

Circuit/System Description

If a malfunction is detected, a DTC will be stored in non-volatile memory. During a side or frontal crash of sufficient force, the inflatable restraint sensing and diagnostic module (SDM) will allow current to flow through the deployment loop in order to deploy the instrument panel (I/P) module. The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. There are 2 shorting bars used within the I/P module connector which will short together both I/P module stage 1 high and low circuits, and both I/P module stage 2 high and low circuits, when the connector is disconnected. This will help to prevent unwanted deployment of the inflator module during servicing.

Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

Conditions for Setting the DTC

B0019 01 Stage 1 or B0020 01 Stage 2

The I/P module high and/or low circuit is short to voltage for 120 milliseconds.

B0019 02 Stage 1 or B0020 02 Stage 2

The I/P module high and/or low circuit is short to ground for 120 milliseconds.

B0019 04 Stage 1 or B0020 04 Stage 2

The I/P module high and/or low circuit is open for 120 milliseconds.

B0019 0D Stage 1 or B0020 0D Stage 2

The I/P module deployment loop resistance is more than 5.1 ohms for 120 milliseconds.

B0019 0E Stage 1 or B0020 0E Stage 2

The I/P module deployment loop resistance is less than 1.3 ohms for 120 milliseconds.

Action Taken When the DTC Sets

    • The SDM commands the AIR BAG indicator ON via serial data communications.
    • The SIR System is disabled and no deployments are allowed.

Conditions for Clearing the DTC

    • The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
    • A history DTC will clear once 255 malfunction-free ignition cycles have occurred.

Reference Information

Schematic Reference

SIR Schematics

Connector End View Reference

SIR Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Special Tools Required

J 38715-A SIR Driver/Passenger Load tool

Circuit/System Testing

Important: Refer to SIR Caution

Important: When removing connectors inspect for damage, corrosion or poor connection. Damage or corrosion in the following requires repair or replacement of the affected component/connector.

   • The air bag module
   • The SDM module
   • The air bag wiring harness connector
   • The SDM wiring harness connector

  1. Ignition OFF, disconnect the harness connector at the I/P air bag module.
  2. With the applicable adaptor, connect J 38715-A .
  3. Ignition ON, with a scan tool, verify the DTC is set as current.
  4. If DTC is not set or is set as history, replace the air bag module.
  5. Ignition OFF, disconnect J 38715-A and the applicable adaptor.
  6. Disconnect the harness connector at the SDM.
  7. Ignition ON, test for less than 1 volt between the HI circuit and ground.
  8. If greater than the specified range, test the circuit for a short to voltage.
  9. Test for less than 1 volt between the applicable LOW circuit and ground.
  10. If greater than the specified range, test the circuit for a short to voltage.
  11. Ignition OFF, test for infinite resistance between the HI circuit and ground.
  12. If not the specified valve, test the circuit for a short to ground.
  13. Test for infinite resistance between the LOW circuit and ground.
  14. If not the specified valve, test the circuit for a short to ground.
  15. Test for less then 1 ohm of resistance between the SDM connector and the air bag module connector HI circuit.
  16. If greater than the specified range, test the circuit for an open/high resistance.
  17. Test for less then 1 ohm of resistance between the SDM connector and the air bag module connector LOW circuit.
  18. If greater than the specified range, test the circuit for an open/high resistance.
  19. If all circuits test normal, replace the SDM.

Repair Instructions

Important: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Inflatable Restraint Instrument Panel Module Replacement
    •  Control Module References for SDM replacement, setup, and programming