For 1990-2009 cars

### 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 B0069: Right Front/Passenger Roof Rail/Head Curtain Bag Deployment Loop Resistance Low
DTC B0070: Right Front/Passenger Roof Rail/Head Curtain Bag Deployment Loop Open
DTC B0071: Right Front/Passenger 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 - Right High Circuit | B0071 | B0071 | B0070 | B0071 | B0069
Roof Rail Module - Right Low Circuit | B0071 | B0071 | B0070 | B0071 | B0069

### Circuit/System Description

The driver roof rail deployment loop consists of an inflatable restraint roof rail module - right 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 diagnostic trouble code (DTC) will be stored in memory.

### Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

### Conditions for Setting the DTC

#### B0069

DTC B0069 will set when the roof rail module-right deployment loop resistance is less than 1.3 ohms for 500 milliseconds.

#### B0070

DTC B0070 will set when one of the following conditions occurs:

• | Roof rail module - right high circuit is less than 2.4 volts and the roof rail module-right deployment loop is more than 6 ohms for 500 milliseconds.

• | Roof rail module - right deployment loop resistance is more than 4.8 ohms for 500 milliseconds.

#### B0071

DTC B0071 when one of the following conditions occur:

• | Roof rail module - right high or low circuits are short to ground or short to voltage for 500 milliseconds.

• | Roof rail module - right high circuit is less than 2.4 volts and roof rail module - right 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 - right high and low circuits

• | An open or a high resistance in the roof rail module - right high or low circuits

• | A short to ground or a short to voltage in the roof rail module - right high or low circuits

• | The roof rail module- right connector

• | The SDM connector

• | A malfunctioning roof rail module

• | A malfunctioning SDM

### Reference Information

#### Schematic Reference

SIR Schematics

#### Connector End View Reference

SIR Connector End Views

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Special Tools Required

• | J 38715-A SIR Driver/Passenger Load Tool

• | EL 38715-125 Load Tool Adapter

### Circuit/System Testing

1. With the ignition OFF, disconnect roof rail module-right connector.
2. Inspect the component and wiring harness sides of connector for the roof rail module-right for damage or corrosion.

⇒ | If the connector for the roof rail module-right is damaged, the roof rail module-right must be replaced.

⇒ | If the roof rail module-right wiring harness side connector is damaged, replace the connector.

3. Use EL 38715-125 adapter to connect the J 38715-A SIR Driver/Passenger Load Tool to the harness side of the roof rail module-right wiring harness connector. Use the PASSENGER INFLATOR connector located on the load tool.
4. With the ignition ON, use a scan tool to observe the SIR DTC display. Verify DTC B0069, B0070, or B0071 are set in history.

⇒ | If DTC B0069, B0070, or B0071 is history replace the roof rail module-right.

5. With the ignition OFF, disconnect and remove the J 38715-A and adapter.
6. Remove the inflatable restraint sensing and diagnostic module (SDM) connector. Inspect the SDM connector for damage or corrosion that may cause a malfunction in the roof rail module-right high and/or low circuits.

⇒ | If damage or corrosion is found make the appropriate repair.

7. Test the high and low circuits between the SDM and roof rail module-right for a short to voltage, short to ground, or open/low resistance.

⇒ | If circuits test good then replace the SDM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Inflatable Restraint Roof Side Rail Module Replacement - Front

• | SIR/SRS Wiring Repairs

• | Control Module References for SDM replacement, setup, and programming