GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2008 🢒 Malibu Classic 🢒 Safety and Security 🢒 Supplemental Inflatable Restraints 🢒 DTC B1370

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 B1370 01: Device Ignition 1 Circuit Short to Battery

DTC B1370 06: Device Ignition 1 Circuit Short to Ground or Open

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Ignition 1 Voltage

B1370 06

B1370 06

B1370 01

B1370 06

Circuit/System Description

The inflatable restraint sensing and diagnostic module (SDM) monitors the ignition 1 voltage signal from the ignition switch. When the vehicle ignition switch is placed in the RUN or CRANK position the switch supplies voltage to the SDM ignition 1 input terminal.

Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

Conditions for Setting the DTC

The following conditions exist for at least 10 seconds:

B1370 01

The SDM detects a short to battery in the ignition 1 voltage circuit when the ignition switch is in the OFF position.

B1370 06

The SDM detects a short to ground or an open/high resistance in the ignition 1 voltage circuit when the ignition switch is in RUN or CRANK.

Action Taken When the DTC Sets
    • The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG indicator.
    • The SDM determines its power mode only from the GMLAN power mode messages and discards the ignition 1 input for the remainder of the ignition cycle.

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

Circuit/System Testing

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

   • SDM module
   • SDM wiring harness connector

  1. Ignition OFF, remove the IGN 1 AIR BAG fuse at the body control module (BCM).
  2. Ignition ON, with a DMM, test for 9-16 volts between the voltage supply side of the AIR BAG fuse and ground.
    3. ⇒If not the specified range, refer to DTC B1370-B1379, B1380-B1389, or B1440-B1443 .
  3. Ignition OFF, disconnect the harness connector at the SDM.
  4. Ignition OFF, test for infinite resistance between the ignition 1 voltage circuit terminal 33 and ground.
    5. ⇒If not the specified value, test the B+ circuit for a short to ground.
  5. Ignition ON, test for less than 1 volt between the ignition 1 voltage circuit terminal 33 and ground.
    6. ⇒If greater than the specified range, test the B+ circuit for a short to voltage.
  6. Ignition OFF, test for less than 1 ohm between the ignition 1 voltage circuit terminal 33 and the AIR BAG fuse terminal A6 X3 at the BCM.
    7. ⇒If greater than the specified range, test the B+ circuit for an open/high resistance.
  7. If all circuits test normal, replace the SDM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  SIR/SRS Wiring Repairs
    •  Control Module References for BCM and SDM replacement, setup, and programming