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Home >> Ford >> 2004 >> Freestar V6-4.2L VIN 2 >> Repair and Diagnosis >> Restraints and Safety Systems >> Air Bag Systems >> Testing and Inspection >> Pinpoint Tests >> Test F
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Test F

PINPOINT TEST F: DTC B1891 - AIR BAG TONE WARNING INDICATOR CIRCUIT SHORT TO BATTERY

Lamp Fault Codes (LFCs)







The lamp fault code (LFC) indicates the specific fault associated with diagnostic trouble code (DTC) B1891.


Test F1:






Test F2:






Test F2-F3:






Test F4:






Test F5:






Normal Operation
The restraints control module (RCM) monitors its connection to the instrument cluster module at C310a pin 23. This connection is used to signal a chime if the air bag indicator is inoperative and another SRS fault exists.

If the RCM detects a short to battery on the connection to the instrument cluster module, it will store diagnostic trouble code (DTC) B1891 in memory and flash lamp fault code (LFC) 10-15 on the air bag indicator.

Possible Causes
An air bag tone warning circuit short to battery or ignition can be caused by:
- faulted wiring, terminals, or connectors.
- a damaged or inoperative instrument cluster module.
- a faulted RCM.
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