For 1990-2009 cars

### Introduction

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 .

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.

### 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. Install a scan tool.

Important: All SIR and PPS DTCs except preload DTCs must be cleared before checking for preload in the PPS.

3. Use the scan tool in order to clear the SIR and PPS DTCs, if any current codes are set except preload DTCs, and then service that DTC first.
4. With the scan tool go to Vehicle Control Systems, then to Module Replacement/Setup, proceed to PPS, and command preload test procedure.
5. Use the scan tool to request the PPS codes. Refer to Passenger Presence System Displaying Code Procedure .
6. If DTC 1052-1055 is present, adjust the seat bottom trim cover to ensure no unwanted pressure is present and restart the preload test.
7. When no preload DTCs are found in the PPS then clear all history DTCs in both the PPS and the SIR System.
8. Perform the Diagnostic System Check - Vehicle after all repairs.