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Test F

PINPOINT TEST F: LFC 17 DTC B1878 - DRIVER PRETENSIONER CIRCUIT SHORT TO VOLTAGE


Test F1-F2:






Test F2-F4:






Test F5:






Normal Operation

NOTE: There is no restraint system diagnostic tool for the safety belt buckle pretensioners. If the ignition switch is turned to the RUN or START position with the safety belt buckle pretensioner electrical connector(s) disconnected, the DTC for an open circuit will be activated.

The restraints control module (RCM) monitors the circuits to the driver safety belt pretensioner for faults. If the RCM detects an unexpected voltage on the driver safety belt pretensioner circuits, it will store diagnostic trouble code (DTC) B1878 in memory and flash, depending on the fault indicator, and lamp fault code (LFC) 17 depending on the fault (or higher priority code if one exists) on the air bag indicator.

Fault Conditions
The RCM monitors for the following fault conditions:
- circuit short to voltage.

Possible Causes
A safety belt pretensioner fault can be caused by:
- damaged wiring, terminals, or connectors.
- a faulted RCM.