Principles of Operation

Seats


Principles of Operation


Front Power Seats

The driver and front passenger power seat motors are hardwired to the seat control switches on each respective front door trim panel. The seat motor circuits are all normally grounded through the seat control switch (rest position). The seat control switch supplies voltage and ground to the appropriate motor on the seat track or recliner motor (if equipped) when a seat adjustment position is selected.


Heated Seats

NOTE: The heater mat on the front passenger seat cushion is not serviceable separately. If a new heater mat is needed on the front passenger seat cushion, a new Occupant Classification Sensor (OCS) system service kit and a new heater mat must be installed. Refer to Air Bag Systems.

NOTE: If a driver seat heater mat (cushion or backrest) or passenger seat backrest heater mat is faulty, a new foam pad must be installed with the new heater mat. Do not reuse the original foam pad.

Vehicles equipped with front heated seats have a heated seat module located under each front seat. The driver and passenger heated seat modules share a common battery voltage supply circuit and a common ignition voltage supply circuit. The engine must be running to operate the heated seat system. When the heated seat switch is pressed, a ground signal is sent to the heated seat module on either the high or low enable circuits to command the system on or off. The heated seat module also supplies ground circuits to the high and low indicators in the heated seat switch. The heated seat module also supplies voltage and ground to the cushion and backrest heater mats. The backrest and cushion heater mats are connected in parallel and operate together. The heated seat module controls the seat temperature by monitoring resistance of a temperature sensor (thermistor) contained within the cushion heater mat and controls the output current to the heater mats. The heated seat module is designed to maintain seat temperature until the system times-out, is switched off or engine is no longer running. The temperature sensor is not serviceable separately, a new sensor must be installed as part of the cushion heater mat or foam pad.