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 provide an overview of each diagnostic category.

DTC Descriptors

DTC B001A 01: Left Front Seat Belt Pretensioner Deployment Loop Short to Battery

DTC B001A 02:  Left Front Seat Belt Pretensioner Deployment Loop Short to Ground

DTC B001A 04: Left Front Seat Belt Pretensioner Deployment Loop Open Circuit

DTC B001A 0D: Left Front Seat Belt Pretensioner Deployment Loop Resistance Above Threshold

DTC B001A 0E: Left Front Seat Belt Pretensioner Deployment Loop Resistance Below Threshold

Diagnostic Fault Information

Circuit

Short to Ground

Low Resistance

High Resistance

Open

Short to Voltage

LF Seat Belt Pretensioner - Low Control

B001A 02

B001A 0E

B001A 0D

B001A 04

B001A 01

LF Seat Belt Pretensioner - High Control

B001A 02

B001A 0E

B001A 0D

B001A 04

B001A 01

RF Seat Belt Pretensioner - Low Control

B001B 02

B001B 0E

B001B 0D

B001B 04

B001B 01

RF Seat Belt Pretensioner - High Control

B001B 02

B001B 0E

B001B 0D

B001B 04

B001B 01

Circuit/System Description

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 seat belt pretensioner - LF. The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage.

A shorting bar used within the seat belt pretensioner - LF connector which will short together both seat belt pretensioner - LF 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

B001A 01

The seat belt pretensioner - LF high and/or low circuit is short to voltage for 120 milliseconds.

B001A 02

The seat belt pretensioner - LF high and/or low circuit is short to ground for 120 milliseconds.

B001A 04

The seat belt pretensioner - LF high and/or low circuit is open for 120 milliseconds.

B001A 0D

The seat belt pretensioner - LF deployment loop resistance is more than 3.9 ohms for 120 milliseconds.

B001A 0E

The seat belt pretensioner - LF deployment loop resistance is less than 1.1 ohms for 120 milliseconds.

Action Taken When the DTC Sets

    • The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG indicator.
    • The SDM will store a DTC, however if an event occurs the system will still attempt deployments.

Conditions for Clearing the DTC

    • The condition for setting the DTC no longer exists.
    • A history DTC will clear once 100 malfunction-free ignition cycles have occurred.

Reference Information

Schematic Reference

SIR Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

SIR System Description and Operation

Electrical Information Reference

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

Scan Tool Reference

Control Module References for scan tool information

Special Tools

Each inflatable restraint module requires a specific adapter to connect the load tool to the SIR system.

    • J 38715-A Driver and Passenger SIR Load Tool
    • J-38715-30A SIR Load Tool Adapter
    • SA9409Z-A SIR Load Tool (Driver/Passenger/Curtain)

Circuit/System Testing

Important: Refer to SIR Service Precautions.

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

   • Inflatable restraint seat belt pretensioner
   • SDM module
   • Front end sensor wiring harness connector
   • SDM wiring harness connector

Important: The connector and connector position assurance (CPA) may seat independent of each other. Both the connector and CPA should seat with an audible and/or tactile click. The CPA isolates the shoring-bars within the connector allowing the deployment circuit to operate properly.

  1. Verify that the LF inflatable restraint seat belt pretensioner connector and CPA are engaged.
  2. If the above condition is not found, make the appropriate repair.
  3. Ignition OFF, disconnect the harness connector at the LF inflatable restraint seat belt pretensioner.
  4. Connect the load tool adaptor SA9409Z-A in place of the LF inflatable restraint seat belt pretensioner.
  5. Ignition ON, with a scan tool, verify that DTC B001A is set as current.
  6. If the DTC is not set or is set as history, cycle the ignition OFF, disconnect the load tool and adapter, reconnect the harness connector at the LF inflatable restraint seat belt pretensioner, and cycle the ignition ON. If the DTC resets after reconnecting the pretensioner, replace the LF inflatable restraint seat belt pretensioner.
  7. Ignition OFF, disconnect the load tool and the adapter.
  8. Disconnect the harness connector at the SDM.
  9. Ignition ON, test for less than 1.0 volt between the low control circuit terminal 24 and ground.
  10. If not within the specified range, test the control circuit for a short to voltage.
  11. Ignition ON, test for less than 1.0 volt between the high control circuit terminal 25 and ground.
  12. If not within the specified range, test the control circuit for a short to voltage.
  13. Ignition OFF, test for infinite resistance between the low control circuit terminal 24 and ground.
  14. If not within the specified range, test the control circuit for a short to ground.
  15. Ignition OFF, test for infinite resistance between the high control circuit terminal 25 and ground.
  16. If not within the specified range, test the control circuit for a short to ground.
  17. Test for less than 1.0 ohm between the low control circuit terminal 1 and the SDM terminal 24.
  18. If not within the specified range, test the control circuit for an open/high resistance.
  19. Test for less than 1.0 ohm between the high control circuit terminal 2 and the SDM terminal 25.
  20. If not within the specified range, test the control circuit for an open/high resistance.
  21. If all circuits test normal, replace the SDM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Driver or Passenger Seat Belt Buckle Replacement
    •  SIR/SRS Wiring Repairs
    •  Control Module References for SDM replacement, setup, and programming