Test D: LFC 25/DTC B1871 - Passenger Air Bag Deactivate Module Fault

PINPOINT TEST D: LFC 25/DTC B1871 - PASSENGER AIR BAG DEACTIVATE MODULE FAULT

D1-D2:

D2-D4:

D4-D6:

D7:

Normal Operation
The restraints control module (RCM) monitors the status of the passenger air bag deactivation (PAD) switch at pin C2041 pin 8, circuit 1112 (WH/LB). The PAD switch signals the RCM by switching a resistance to ground. If the RCM senses 900-1100 ohms in the PAD switch, it enables the passenger air bag and turns off the PAD switch warning lamp. If the RCM senses 400-600 ohms in the PAD switch, it deactivates the passenger air bag and turns the PAD switch warning lamp on. If the RCM detects an invalid resistance, it will store a diagnostic trouble code (DTC) B1871 in memory and flash a lamp fault code (LFC) 25 (or higher priority code if one exists) on the air bag indicator.

Possible Causes
A PAD switch fault could be caused by:
- wiring, terminals or connectors.
- a faulted PAD switch.
- a faulted RCM.
- an incorrectly configured RCM.