Tech Tip: How to repair an Expedition with MIL and airbag lights on

When the technician called ALLDATA Tech-Assist, he was advised that the airbag system on this vehicle uses the seat track position to determine the airbag ignition deployment force.

Related To:

ALLDATA Corp.

Sept. 28, 2020

Vehicle: 2003 Ford Expedition, 4WD, V8-5.4L SOHC, VIN L

Mileage: 178,262

Problem: This vehicle was brought to the shop because the malfunction indicator light (MIL) and the airbag warning light were on.

Case Details: The technician connected a scan tool to check for diagnostic trouble codes (DTCs). He retrieved only one DTC:

C1981 – Seat track position sensor circuit fault

When the technician called ALLDATA Tech-Assist, he was advised that the airbag system on this vehicle uses the seat track position to determine the airbag ignition deployment force. If there is a seat track position error, the airbag system will show a fault. The consultant further advised that It would be best to begin the diagnosis by removing the seat to check for continuity between the sensors and connectors. While testing the circuits, the technician found an open wire between pin 23 of the restraints control module (in connector C313) and pin 2 of the seat position sensor, driver (in connector C356).

Confirmed Repair: The technician repaired the open wire, cleared the DTC, cycled the seat back and forth a few times and test drove the vehicle. The airbag light did not return.

Information provided by ALLDATA