Diagnostic Instructions
DTC Descriptors
DTC B0064 : Left Front/Driver Pretensioner Deployment Loop Resistance Low
DTC B0065 : Left Front/Driver Pretensioner Deployment Loop Open
DTC B0066 : Left Front/Driver Pretensioner Deployment Loop Voltage Out of Range
Diagnostic Fault Information
Circuit
| Short to Ground
| High Resistance
| Open
| Short to Voltage
| Signal Performance
|
Seat Belt Pretensioner - LF High Circuit
| B0066
| B0066
| B0065
| B0066
| B0064
|
Seat Belt Pretensioner - LF Low Circuit
| B0066
| B0066
| B0065
| B0066
| B0064
|
Circuit/System Description
The driver seat belt pretensioner deployment loop consists of a seat belt pretensioner - LF and the seat belt pretensioner - LF high and low circuits. A shorting bar used within the seat belt pretensioner connector shorts together both the
seat belt pretensioner high and low circuits when the connector is disconnected. This will help to prevent unwanted deployment of the pretensioner during servicing. During a 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 seat belt pretensioner. 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
B0064
The DTC will set when the seat belt pretensioner - LF deployment loop resistance is less than 1.3 ohms for 500 milliseconds.
B0065
The DTC will set when one of the following conditions occurs:
• | Seat belt pretensioner - LF high circuit is less than 2.4 volts and the seat belt pretensioner - LF deployment loop is more than 6 ohms for 500 milliseconds. |
• | Seat belt pretensioner - LF deployment loop resistance is more than 4.8 ohms for 500 milliseconds. |
B0066
The DTC when one of the following conditions occur:
• | Seat belt pretensioner - LF high or low circuits is short to ground or short to voltage for 500 milliseconds. |
• | Seat belt pretensioner - LF high circuit is less than 2.4 volts and seat belt pretensioner - LF 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 seat belt pretensioner - LF high and low circuits |
• | An open or a high resistance in the seat belt pretensioner - LF high or low circuits |
• | A short to ground or a short to voltage in the seat belt pretensioner - LF high or low circuits |
• | The seat belt pretensioner - LF connector |
• | A malfunctioning seat belt pretensioner |
Reference Information
Schematic Reference
SIR Schematics
Connector End View Reference
SIR Connector End Views
Electrical Information Reference
Special Tools Required
• | J 38715-30A Load Tool Adapter |
Circuit/System Testing
- With the ignition OFF, disconnect seat belt pretensioner connector. Refer to
Seat Belt Retractor Pretensioner Replacement - Front
for location of connector.
- Inspect the component and wiring harness sides of connector for the seat belt pretensioner for damage or corrosion.
⇒ | If the connector for the seat belt pretensioner is damaged, the seat belt pretensioner must be replaced. |
⇒ | If the seat belt pretensioner wiring harness side connector is damaged, replace the connector. |
- Use J 38715-30A to connect the
J 38715-A
to the harness side of the seat belt pretensioner 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 B0064, B0065, or B0066 are set in history.
⇒ | If DTC B0064, B0065, or B0066 is history, replace the seat belt pretensioner. |
- With the ignition OFF, disconnect and remove the
J 38715-A
and adapter.
- Remove the inflatable restraint SDM connector. Inspect the SDM connector for damage or corrosion that may cause a malfunction in the seat belt pretensioner high and/or low circuits. Refer to SDM replacement in repair instructions for connector location.
⇒ | If damage or corrosion is found, make the appropriate repair. |
- Test the high and low circuits between the SDM and seat belt pretensioner 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.