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Test E: LFC 33/DTC B1878 - Driver Pretensioner Circuit Short to Battery

PINPOINT TEST E: LFC 33/DTC B1878 - DRIVER PRETENSIONER CIRCUIT SHORT TO BATTERY


E1-E2:






E2-E4:






E5:






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.

Normal Operation
The safety belt pretensioners are activated by the RCM to remove excessive slack from the safety belt webbing when an impact exceeding preprogrammed limits is detected.

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 lamp fault code (LFC) 33 (or higher priority code if one exists) on the air bag indicator.

Fault Conditions
The RCM monitors for the following fault condition:
- Circuit short to voltage

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