Occupant Classification Sensor (OCS) System

WARNING: This page is about a different car, the 2008 Mercury Mariner and 2008 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: It is necessary to carry out the occupant classification sensor (OCS) system reset when a front passenger seat cushion is disassembled, a new trim cover installed or an OCS service kit is installed. A scan tool is used to trigger the active command to carry out the OCS system reset.

NOTE: To identify between a production occupant classification sensor (OCS) system and a OCS system service kit, inspect the occupant classification system module (OCSM) electrical connector.

A production OCS system allows the disconnect of the electrical connector from the OCSM.

An OCS system service kit has the OCSM electrical connector glued to the module. It cannot and should not be disconnected or altered.

The OCS system is found only on the front passenger seat. The front passenger seat OCS system is comprised of a silicone gel-filled bladder mounted between the seat cushion foam and pan, a pressure sensor that is mounted to the seat frame and an occupant classification system module (OCSM) which is also mounted to the seat frame. Pressure is applied to the OCS system bladder when weight of any occupant or object in the front passenger seat is present. The pressure is then transferred through a tube, is sensed by the OCS system pressure sensor, then electronically communicated to the OCSM. Based on preprogrammed set points the OCSM will inform the restraints control module (RCM), via a high-speed controller area network (HS-CAN), of the necessary information. The RCM uses this information in determining if the passenger air bag module is to be deployed in the event of a deployable collision. The RCM may also use this information to illuminate/not illuminate the passenger air bag deactivation (PAD) indicator. For information regarding PAD indicator operation, refer to Passenger Air Bag Deactivation Indicator in this article.

The OCSM monitors the OCS system for faults and communicates on-demand and continuous DTCs via the data link connector (DLC) with the use of a scan tool.

The OCS system also interprets a variable voltage signal provided by the safety belt tension sensor to identify the presence of a cinched child safety seat in the front outboard passenger seat installed according to manufacturer instructions. The OCSM then communicates with the RCM, automatically deactivating the passenger air bag module. Refer to Safety Belt Tension Sensor in this article.

The OCS system is also used for operation of the passenger Belt Minder®. For information on the passenger Belt Minder® feature, refer to SAFETY BELT SYSTEM article. To deactivate or reactivate the passenger Belt Minder® feature, refer to INSTRUMENT CLUSTER (IC), MESSAGE CENTER, AND WARNING CHIMES article or the Owner's Literature.

When an OCS system fault is present, the air bag warning indicator lamp will illuminate or the air bag warning chime will be activated (if an air bag warning indicator fault is present). The supplemental restraint system (SRS) then defaults the passenger air bag module to ON (activated) regardless of the size of the occupant in the front outboard passenger seat.

The OCS system components (seat cushion foam pad, bladder with pressure sensor, seat wiring harness and OCSM) are calibrated to each other and are serviced as an assembly. OCS system components are not to be installed separately.