Heated Seats

WARNING: This page is about a different car, the 2009 Ford Mustang. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION: Do not install a new heater mat on a front passenger seat cushion. If a new cushion heater mat is needed on the front passenger seat, an occupant classification sensor (OCS) service kit equipped with a heater mat must be installed. Failure to follow this instruction may result in incorrect operation of the OCS system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM for the OCS removal and installation procedure.

The driver and passenger heated seats share a common battery voltage circuit to the heated seat relay junction box. The ignition switch supplies circuit voltage to the logic board and illumination of the heated seat switches located on the heating ventilation air conditioning (HVAC) module. Battery voltage is supplied to the heater mats.

There are 2 voltage supply circuits to the heated seat relay. One circuit energizes the heated seat relay and heated seat switch indicator when the ignition switch is in the RUN position and heated seat switch is activated. This closes the relay switching voltage to the cushion and backrest heater mats from the other voltage supply circuit. The heated seat will remain on until the heated seat switch is selected off or a 10-minute time-out period occurs. If ignition switch is cycled OFF, the heated seat system is off.

Each seat's cushion and backrest heater mats are wired in series circuits. Seat temperature is maintained using a bi-metallic thermostat in each cushion heater mat which opens and closes, switching voltage on and off to the heater mats.