GM Service Manual Online
For 1990-2009 cars only

Introduction

The passenger presence system (PPS) is a calibrated system that requires rezeroing when the system has been serviced or replaced. The procedures below are designed to assist in the rezeroing of the PPS. Before you start, read these procedures carefully and completely. For further information regarding the PPS refer to SIR System Description and Operation .

Important: The following procedures must be followed:

    • Read this procedure carefully and completely.
    • The PPS will not function properly if the PPS rezeroing procedure is not performed.
    • Perform the Diagnostic System Check - Vehicle after successfully completing the rezeroing procedure to ensure the system is functioning properly.

Important: The PPS requires rezeroing after any of the following:

    • Replacement of the PPS module
    • Installation of any seat accessories
    • Removal and installation of the seat
    • Illumination of both the air bag indicator and the passenger air bag OFF indicator
    • After a collision

Passenger Presence System (PPS) Rezeroing Procedure

Tools Required

EL-47729 Passenger Presence Seat Weights

Important: Before rezeroing the PPS, the front passenger seat must be completely empty of all items. The presence of any items on the front passenger seat will affect the calibration and operation of the PPS.

  1. Empty the front outboard passenger seat.
  2. Verify that all SIR and PPS components, connectors and connector position assurances (CPAs) are properly connected and mounted.
  3. Position the seat as follows:
  4. • Seat at the rearmost position
    • Seat back in upright position
    • Headrest at its lowest position
    • Seat at its lowest position
  5. Install a scan tool.
  6. Turn ON the ignition, with the engine OFF.
  7. Important: All SIR and PPS DTCs must be cleared before rezeroing the PPS. The presence of current or history DTCs will prevent the PPS from rezeroing and may set additional DTCs.

  8. Use the scan tool in order to clear the SIR and PPS DTCs.
  9. With a scan tool, request the Zero Point Calibration procedure.
  10. Initiate the zero Point Calibration procedure.
  11.    Important: The Sensitivity Check requires the use of EL-47729 Passenger Presence Seat Weights.

    • When the rezeroing procedure has been completed, the sensitivity check must be performed as prompted on the scan tool.

    Sensitivity Check
    27-33 kg (59.52-72.75 lbs)

    • If the sensitivity check was not within specification, retighten the passenger seat bolts. Refer to Fastener Tightening Specifications . If after tightening the seat bolts the sensitivity is not within specification, replace the seat adjuster frame. Refer to Front Seat Cushion Frame Replacement .
  12. If the rezeroing procedure was unsuccessful repeat this procedure. If the rezeroing procedure is unsuccessful a second time, replace the seat adjuster frame. Refer to Front Seat Cushion Frame Replacement .
  13. After the PPS has been successfully rezeroed perform the Diagnostic System Check - Vehicle .