Vehicles Built 03/2002 Onward

PRINCIPLES OF OPERATION - HEATED SEATS - VEHICLES BUILT 03/2002 ONWARD

NOTE: Two heated seat modules are used, one for vehicles built up to 03/2002 and one for vehicles built 03/2002 onward. The modules are not interchangeable.

The driver and passenger heated seats share a common battery and ignition feed. A shared ground source supplies the heated seat control switches. When the heated seat control switch is pressed with the ignition switch in RUN or START, a momentary ground signal is sent to the heated seat module. The heated seat module then supplies power to the heating element circuit. The cushion element and seat backrest element are wired in series and powered by the same output. The heated seat module will supply voltage to a separate indicator circuit to the dual automatic temperature control (DATC) module display panel to indicate an ON state. The heated seat module will remain on until the heated seat control switch is pressed and a momentary voltage signal is received, or until 10 minutes expire. If the ignition source is removed from the module, the heated seat module will enter an OFF state and will not return to ON until the switch is once again pressed with the ignition switch in RUN. The heated seat module is designed to heat the seat to 37.5°C (99.5°F) and maintain the temperature until time-out or switched off. This temperature is maintained by the heated seat module monitoring the temperature sensor located in the seat cushion element, and adjusting the current flow to the heating elements.