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 BatteryDTC B1370 06: Device Ignition 1 Circuit Short to Ground or Open
Circuit | Short to Ground | High Resistance | Open | 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. If an open, short to voltage, 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 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 switch is in the OFF position.
B1370 06
The SDM detects a short to ground or an open 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
Connector End View Reference
Description and Operation
SIR System Description and Operation
Electrical Information Reference
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
- Ignition OFF, remove the IGN 1 AIR BAG fuse at the body control module (BCM).
- Ignition ON, with a DMM, test for 9-16 volts between the voltage supply side of the AIR BAG fuse and ground.
- Ignition OFF, disconnect the harness connector at the SDM.
- Ignition OFF, test for infinite resistance between the ignition 1 voltage circuit terminal 33 and ground.
- Ignition ON, test for less than 1.0 volt between the ignition 1 voltage circuit terminal 33 and ground.
- Ignition OFF, test for less than 1.0 ohm between the ignition 1 voltage circuit terminal 33 and the AIR BAG fuse terminal A6 X3 at the BCM.
- If all circuits test normal, replace the SDM.
| ⇒ | If not the specified range, refer to DTC B1370-B1379, B1380-B1389, or B1440-B1443 . |
| ⇒ | If not the specified value, test the B+ circuit for a short to ground. |
| ⇒ | If greater than the specified range, test the B+ circuit for a short to voltage. |
| ⇒ | If greater than the specified range, test the B+ circuit for an open/high resistance. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM and SDM replacement, setup, and programming |
