Inflatable Restraint Passenger Presence System (PPS)

WARNING: This page is about a different car, the 2007 Cadillac DTS. However, it is still accessible from the selected car via links, so may be relevant.

IMPORTANT: The Passenger Presence System (PPS), heated seat element (if equipped), and the seat bottom foam cushion is a calibrated unit and cannot be service separately. After repairing or replacing the PPS, the system must be rezeroed in order to function properly. The seat belt tension sensor, part of the PPS, is serviced separate from the PPS and is integral to the seat belt buckle.

The PPS is used to monitor the weight of an occupant on the front outboard passenger seat and communicate the status to the sensing and diagnostic module (SDM) whether to enable or suppress the deployment of the instrument panel (I/P) module and the right front side impact module. The PPS consist of an electronic control module, silicone filled sensor pad, pressure sensor, seat belt tension sensor, wiring harness, and PASSENGER AIR BAG ON/OFF indicators. The silicone filled sensor pad is located under the passenger seat foam cushion and is connected by a hose clamped to the pressure sensor. The weight of the occupant sitting in the front passenger seat is measured as a pressure change within the bladder by the pressure sensor. The pressure sensor sends a voltage signal to the PPS module. If the pressure from the occupants weight is less than a specified value, the PPS module will send a suppress signal to the SDM to disable the I/P and the right front side impact modules. If the pressure from the occupants weight is higher than a specified value, the PPS module will send an enable signal to the SDM to enable the I/P and the right front side impact modules. The inflatable restraint seat belt tension sensor is mounted within the buckle of the passenger seat belt and provides an input to the PPS. When an infant car seat is properly restrained on the front passenger seat, the seat belt is tightly secured through the car seat. The seat belt pulls on the tension sensor and changes the voltage signal to the PPS module. When the PPS determines a child safety seat is present, it will request that the SDM suppress the deployment of the I/P module and turn the passenger air bag OFF indicator ON. In addition, the SDM may also disable the passenger side and roof rail air bags. The PPS monitors itself, including it sensors for faults and will set a DTC if a fault is detected. Using serial data communications, the PPS will notify the SDM of a fault and the SDM will suppress the deployment of the I/P module and request the instrument panel cluster (IPC) to turn ON the AIR BAG indicator located on the IPC and the passenger air bag OFF indicator. By turning ON either the ON or OFF indicators, the customer is notified of the enable/disable status.