Test Notes

Normal Operation
The air bag Electronic Crash Sensor (ECS) module monitors the status of the Passenger Air Bag Deactivation (PAD) switch at Pin C250-9, Circuit 1112 (W/LB). The PAD switch signals the ECS by switching a resistance to ground. If the ECS senses 900-1100 ohms in the PAD switch, it enables the passenger air bag and turns off the PAD switch warning lamp. If the ECS senses 400-600 ohms in the PAD switch, it deactivates the passenger air bag and turns the PAD switch warning lamp on. If the ECS 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 damaged or inoperative PAD switch.
^ a damaged or inoperative ECS module.
^ a short to battery, short to ground or open on Circuit 1112 (W/LB).