GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2007 🢒 STS 🢒 Safety and Security 🢒 Supplemental Inflatable Restraints 🢒 Passenger Presence System Preload Test

Introduction

Important: The following steps must be followed:

  1. Read this procedure carefully and completely.
  2. The PPS will not function properly if the PPS detects a preload within a region.
  3. Perform the Diagnostic System Check - Vehicle , after successfully completing the preload test procedure to ensure the system is functioning properly.

The Passenger Presence System (PPS) is a calibrated system that requires checking for preloads within each region when the system has been serviced or replaced. If the passenger seat bottom cushion or seat bottom trim has been serviced, reinstalled, or removed for any reason, the procedure below was designed to assist in checking for preloads 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 .

Passenger Presence System Preload Test Procedure

Important: 

   • Before checking for preload in 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 this procedure.
   • When the sensing and diagnostic module (SDM) starts to communicate with the PPS, the instrument panel cluster (IPC) and dash lights will begin dimming on and off. This is normal operation during this procedure and does not indicate additional system faults.

  1. Empty the front outboard passenger seat.

    2. Important: If preload DTCs are set in the PPS, the SDM will set DTC B0081 when the ignition is turned ON. This code must be cleared with the ignition OFF before continuing with the preload test by doing the following:

    1. Switch the ignition to the OFF position.
    2. Disconnect the scan tool for 60 seconds.
    3. Ignition OFF, connect scan tool and clear SIR DTCs.

  2. Verify no PPS or SIR DTCs exist except for preload. If any current codes are set except preload DTCs, diagnose those DTCs first.

    3. Important: 

       •  During the preload test the scan tool will ask if both passenger air bag indicators are illuminated. The passenger airbag indicators will only illuminate for 5 seconds.
       • When the preload test completes, the scan tool may display Unable to Clear DTCs. If this message is displayed, restart the preload test from the beginning. This message does not directly indicate that a preload or module failure exists.

  3. With a scan tool, command the preload test procedure and follow the on screen instructions.
  4. If the scan tool displays Test Failed, request PPS DTCs. Refer to Passenger Presence System Displaying Code Procedure .
  5. If DTC 1052-1055 is present, adjust the seat bottom trim cover and massage the seat cushion to ensure no unwanted pressure is present and restart the preload test.
  6. When no preload DTCs are found in the PPS then clear all history DTCs in both the PPS and the SIR systems.