Normal Operation

The driver seat is equipped with a seat track position sensor. The seat track position sensor is comprised of integrated circuits called a Hall-effect switch. The seat track position sensor indicate to the Restraints Control Module (RCM) the position of the driver seat, forward or rearward.

The RCM  supplies current to the seat track position sensor. Current flows through the switch, both in the forward or rearward seat position to ground. The RCM  will sense the difference in this current draw, 3 mA (forward) or 8 mA (rearward), and use this information in determining the deployment rate of the dual-stage driver air bag module.

If the RCM  detects an open circuit or a short to battery on the driver seat track position sensor, it will store DTC C1981 in memory and send a message to the Instrument Cluster (IC) module to flash a Lamp Fault Code (LFC) 49 on the air bag warning indicator. After the LFCs  are displayed, the air bag warning indicator will remain illuminated for the rest of the ignition cycle.

• DTC C1981 (Front Driver's Seat Track Position Switch Circuit Fault) - If the RCM  detects an open or short to battery on the driver seat track position sensor circuit for greater than 2.5 seconds, it will set this DTC. An open driver seat track position switch ground circuit can set this DTC.

  This pinpoint test is intended to diagnose the following: 

• Wiring, terminals or connectors
• RCM