2014 Jeep Wrangler JK Factory Service Manual 10 - Restraints

SENSOR, Seat Track Position

DESCRIPTION

The Seat Track Position Sensor (STPS) (2) is a Hall Effect-type sensor used on some vehicles. This sensor consists of a Hall Effect Integrated Circuit (IC) chip encased in potting material within a cavity of the molded plastic sensor housing.

The STPS housing has a mounting slot containing an integral latch feature (1) and slides and latches onto a stamped metal blade-type bracket located on the inboard side of the upper inboard seat adjuster track near the rear of both the passenger and driver front seats. A molded connector receptacle (3) integral to the STPS housing is connected to the vehicle electrical system through a connector and take out of the seat wire harness beneath the front seat cushion frame.

The STPS cannot be adjusted or repaired and, if ineffective or damaged, the entire STPS unit must be replaced.

OPERATION

The Seat Track Position Sensor (STPS) is designed to provide a seat position data input to the Occupant Restraint Controller (ORC) indicating whether the driver or passenger front seat is in a full forward or a not full forward position. The ORC uses this data as an additional logic input for use in determining the appropriate deployment force to be used when deploying the multistage Driver AirBag (DAB).

The STPS receives a nominal five volt supply from the ORC. The STPS communicates the seat position by modulating the voltage returned to the ORC on a sensor data circuit. The ORC also monitors the condition of the STPS circuits and will store a Diagnostic Trouble Code (DTC) for any fault that is detected. The ORC then sends messages over the CAN data bus to control the illumination of the airbag indicator in the ElectroMechanical Instrument Cluster (EMIC) (also known as the Cab Compartment Node/CCN).

The hard wired circuits between the STPS and the ORC may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. However, conventional diagnostic methods will not prove conclusive in the diagnosis of the STPS or the electronic controls and communication between other modules and devices that provide features of the Supplemental Restraint System (SRS). The most reliable, efficient and accurate means to diagnose the STPS or the electronic controls and communication related to STPS operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.

REMOVAL

WARNING:

To avoid serious or fatal injury on vehicles equipped with airbags, disable the Supplemental Restraint System (SRS) before attempting any steering wheel, steering column, airbag, seat belt tensioner, impact sensor or instrument panel component diagnosis or service. Disconnect and isolate the battery negative (ground) cable, then wait two minutes for the system capacitor to discharge before performing further diagnosis or service. This is the only sure way to disable the SRS. Failure to take the proper precautions could result in accidental airbag deployment.


  1. Disconnect and isolate the negative cable from the battery. Wait two minutes for the system capacitor to discharge before further service.

    2.  
  2. Reach under the front seat cushion to access the Seat Track Position Sensor (STPS) (2) on a bracket (1) located on the inboard side near the rear of the upper inboard seat track (4).

    3.  
  3. Using a small screwdriver, hold the latch feature (3) depressed while sliding the connector end of the STPS off of the bracket.

    4.  
  4. Disconnect the seat wire harness connector (5) from the STPS connector receptacle.

    5.  
  5. Remove the STPS from under the front seat.

    6.  

INSTALLATION

WARNING:

To avoid serious or fatal injury on vehicles equipped with airbags, disable the Supplemental Restraint System (SRS) before attempting any steering wheel, steering column, airbag, seat belt tensioner, impact sensor or instrument panel component diagnosis or service. Disconnect and isolate the battery negative (ground) cable, then wait two minutes for the system capacitor to discharge before performing further diagnosis or service. This is the only sure way to disable the SRS. Failure to take the proper precautions could result in accidental airbag deployment.


  1. Reach under the front seat cushion to reconnect the seat wire harness connector (5) to the Seat Track Position Sensor (STPS) (2) connector receptacle. Be certain that the latch on the connector is fully engaged.

    2.  
  2. Align the open end of the STPS to the slide tab of the STPS bracket (1) located on the inboard side near the rear of the upper inboard seat track (4).

    3.  
  3. Push the STPS firmly onto the bracket until the latch feature (3) snaps into place with an audible click.

    4.  
  4. Do not reconnect the negative cable to the battery at this time. The Supplemental Restraint System (SRS) Verification Test procedure should be performed following service of any SRS component. (Refer to 10 - Restraints - Standard Procedure) .

    5.