B0091 3A
* The SDM has received an ID message from the front end sensor, which does not match the ID stored in the SDM memory.
* The SDM has reset the front end sensor twice without detecting the correct ID message.
B0091 71
The SDM has received invalid serial data from the front end sensor.
Action Taken When the DTC Sets
* The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG indicator.
* The frontal SIR System is disabled and no frontal deployments are allowed. Side deployments and rollover detection is still enabled.
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 (See: Diagrams/Electrical Diagrams/Air Bag Systems)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
SIR System Description and Operation (See: Restraints and Safety Systems/Air Bag Systems/Description and Operation)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
Scan Tool Reference
Control Module References (See: Testing and Inspection/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 component/connector:
* Front end sensor
* SDM module
* Front end sensor wiring harness connector
* SDM wiring harness connector
1. Ignition OFF, disconnect the front end sensor harness connector. Refer to front end sensor replacement for location of connector.
2. Remove the SDM harness connector. Refer to SDM replacement for location of connector.
3. Test for infinite resistance between the front end sensor signal circuit terminal 1 and ground.
锟斤拷 If less than the specified value, test the circuit for a short to ground.
4. Ignition ON, test for less than 1 volt between the front end sensor signal circuit terminal 1 and ground.
锟斤拷 If greater than the specified range, test the circuit for a short to voltage.
5. Ignition ON, test for less than 1 volt between the front end sensor low reference circuit terminal 2 and ground.
锟斤拷 If greater than the specified range, test the circuit for a short to voltage.
