Operation CHARM: Car repair manuals for everyone.

Heated Seat

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 also will supply voltage to the separate indicator circuits at the heated seat switch to indicate an ON state. The heated seat module will remain on until the heated seat control switch is pressed and a momentary ground 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.