Supplemental Inflatable Restraints
DTC B1370
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using the diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.
DTC Descriptors
DTC B1370 06
- Device Ignition 1 Circuit Short to Ground or Open
Circuit/System Description
The inflatable restraint sensing and diagnostic module (SDM) monitors the ignition 1 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. If an open or short to ground in this SDM ignition 1 circuit is detected, then DTC B1370 will set.
Conditions for Running the DTC
Ignition voltage is between 9-16 volts.
Conditions for Setting the DTC
The SDM detects a short to ground or an open in the ignition 1 voltage circuit for at least 10 seconds when the ignition switch is in RUN or CRANK .
Action Taken When the DTC Sets
* The SDM commands the AIR BAG indicator ON via serial data communications.
* 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 responsible for setting the DTC no longer exists.
* A history DTC will clear once 255 malfunction-free ignition cycles have occurred.
Reference Information
Schematic Reference
SIR Schematics ([1][2]Air Bag Systems)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
SIR System Description and Operation (Description and Operation)
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
Scan Tool Reference
Programming and Relearning (Programming and Relearning) for scan tool information.
Circuit/System Testing
Important: When removing connectors inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected.
* SDM
* SDM wiring harness
1. Ignition OFF, remove the IGN 1 AIR BAG fuse.
2. Ignition ON, with a DMM, test for 9-16 V between the voltage supply side and ground.
• If not the specified range, refer to DTC B1370 (B1370) .
3. Ignition OFF, disconnect the harness connector at the SDM.
4. Ignition OFF, disconnect the X2 harness connector at the IP fuse block.
5. Ignition OFF, test for less then 1 ohm of resistance between the ignition 1 voltage circuit terminal 32 and the IP fuse block terminal 10 (X2).
• If greater then the specified range, test the circuit for an open/high resistance.
6. Ignition ON, test for less then 1 volt between the ignition 1 voltage circuit terminal 32 and the IP fuse block terminal 10 (X2).
• If greater then the specified value, test the circuit for a short to voltage.
7. If all circuits test normal, replace the SDM.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Programming and Relearning (Programming and Relearning) for SDM replacement, setup, and programming
* SIR/SRS Wiring Repairs (Component Tests and General Diagnostics)