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 B0061 : Left Front/Driver Roof Rail/Head Curtain Bag Deployment Loop Resistance LowDTC 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 | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance |
|---|---|---|---|---|---|
Roof Rail Module - Left High Circuit | B0068 | B0068 | B0062 | B0068 | B0061 |
Roof Rail Module - Left Low Circuit | B0068 | B0068 | B0062 | B0068 | B0061 |
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
The DTC 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
The DTC 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 and the scan tool Clear DTC function is used. |
| • | A history DTC will clear once 255 malfunction-free ignition cycles have occurred. |
Diagnostic Aids
If there is more than one DTC set, diagnose the open DTC first. The following are possible causes of the malfunction:
| • | A short between the roof rail module - left high and low circuits |
| • | An open or a high resistance in the roof rail module - left high or low circuits |
| • | A short to ground or a short to voltage in the roof rail module - left high or low circuits |
| • | The roof rail module - left connector |
| • | The SDM connector |
| • | A malfunctioning roof rail module |
| • | A malfunctioning SDM |
Reference Information
Schematic Reference
Connector End View Reference
Electrical Information Reference
Special Tools Required
| • | J 38715-A SIR Driver/Passenger Load tool |
| • | J 38715-30A Load Tool Adapter |
Circuit/System Testing
- With the ignition OFF, disconnect roof rail module - left connector. Refer to Inflatable Restraint Roof Side Rail Module Replacement - Front for location of connector.
- Inspect the component and wiring harness sides of connector for the roof rail module - left for damage or corrosion.
- Use J 38715-30A to connect the J 38715-A to the harness side of the roof rail module - left wiring harness connector. Use the PASSENGER INFLATOR connector located on the load tool.
- With the ignition ON, use a scan tool to observe the SIR DTC display. Verify DTCs B0061, B0062, or B0068 are set in history.
- With the ignition OFF, disconnect and remove the J 38715-A and adapter.
- Remove the SDM connector. Inspect the SDM connector for damage or corrosion that may cause a malfunction in the roof rail module - left high and/or low circuits. Refer to SDM replacement in repair instructions for connector location.
- Test the high and low circuits between the SDM and roof rail module - left for a short to voltage, short to ground, or open/low resistance.
| ⇒ | If the connector for the roof rail module - left is damaged, the roof rail module - left must be replaced. |
| ⇒ | If the roof rail module - left wiring harness side connector is damaged, replace the connector. |
| ⇒ | If DTC B0061, B0062, or B0068 is history replace the roof rail module - left. |
| ⇒ | If damage or corrosion is found, make the appropriate repair. |
| ⇒ | If circuits test good, then replace the SDM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for SDM replacement, setup, and programming |
