B0068
DTC B0061, B0062, or B0068
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC B0061
- Left Front/Driver Roof Rail/Head Curtain Bag Deployment Loop Resistance Low
DTC B0062
- Left Front/Driver Roof Rail/Head Curtain Bag Deployment Loop Open
DTC B0068
- Left Front/Driver Roof Rail/Head Curtain Bag Deployment Loop Voltage Out of Range
Diagnostic Fault Information
Circuit/System Description
The driver roof rail deployment loop consists of an inflatable restraint roof rail module - left and the roof rail module high and low circuits. A shorting bar used within the roof rail module connector shorts together both the roof rail module high and low circuits when the connector is disconnected. This will help to prevent unwanted deployment of the inflator module during servicing. 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 roof rail module. The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. If a malfunction is detected, a DTC will be stored in memory.
Conditions for Running the DTC
Ignition voltage is between 9-16 volts.
Conditions for Setting the DTC
B0061
The DTC will set when the roof rail module - left deployment loop resistance is less than 1.3 ohms for 500 milliseconds.
B0062
This DTC will set will set when one of the following conditions occurs:
* Roof rail module - left high circuit is less than 2.4 volts and the roof rail module - left deployment loop is more than 6 ohms for 500 milliseconds.
* Roof rail module - left deployment loop resistance is more than 4.8 ohms for 500 milliseconds.
B0068
This DTC will set when one of the following conditions occur:
* Roof rail module - left high or low circuit is short to ground or short to voltage for 500 milliseconds.
* Roof rail module - left high circuit is less than 2.4 volts and roof rail module - left deployment loop resistance is less than 6 ohms for 500 milliseconds.
Action Taken When the DTC Sets
* The SDM commands the AIR BAG indicator ON via class 2 serial data.
* The SIR system is disabled and no deployments are allowed.
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 (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Special Tools
* J 38715-A SIR Driver/Passenger Load Tool
* J 38715-30A Load Tool Adapter
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.
* The left roof rail module
* The SDM
* The left roof rail module wiring harness connector
* The SDM wiring harness connector
1. Ignition OFF, disconnect harness connector at the left roof rail module.
2. Use J 38715-30A to connect the J 38715-A to the harness side of the left roof rail module. Use the PASSENGER INFLATOR connector located on the load tool.
3. Ignition ON, verify B0061, B0062, or B0068 is set current.
• If B0051, B0052, or B0068 is history replace the left roof rail module.
4. Ignition OFF, disconnect and remove the J 38715-A .
5. Disconnect the harness connector at the SDM.
6. Test for infinite resistance between the left roof rail module circuit terminal A and ground.
• If less than the specified range, test the circuit for a short to ground.
7. Test for infinite resistance between the left roof rail module circuit terminal B and ground.
• If less than the specified range, test the circuit for a short to ground.
8. Ignition ON, test for less than 1 volt between the left roof rail module control circuit terminal A and ground.
• If greater than the specified range, test the control circuit for a short to voltage.
9. Test for less than 1 volt between the left roof rail module control circuit terminal B and ground.
• If greater than the specified range, test the control circuit for a short to voltage.
10. Ignition OFF, test for less then 1 ohm between the left roof rail module terminal A and SDM signal circuit terminal 13.
• If greater than the specified range, test the circuit for an open/high resistance.
11. Test for less then 1 ohm between the left roof rail module terminal B and SDM voltage circuit terminal 12.
• If greater than the specified range, test the circuit for an open/high resistance.
12. If all circuits test normal, replace the SDM.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* SIR/SRS Wiring Repairs (SIR/SRS Wiring Repairs)
* Inflatable Restraint Roof Side Rail Module Replacement - Front (Inflatable Restraint Roof Side Rail Module Replacement - Front)
* Control Module References (Programming and Relearning) for SDM replacement, setup, and programming