Heated Seats System Operation

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Both the driver and passenger seats have 2 heating elements. One is in the seat cushion and the other is in the seat back. The heated seats are capable of obtaining temperatures of 98°F in LOW mode and 107°F in HIGH mode. Battery voltage is supplied to the heated seat module from the SEO2 30A fuse and through a PTC device. The PTC is hardwired in the battery voltage supply circuit in the seat harness assembly and provides extra circuit protection. Ignition voltage is supplied to the heated seat switch from the IGN3 10A fuse. When the heated seat switch is pressed ignition voltage is supplied to the solid state switching device within the heated seat switch assembly.

The first time the heated seat switch is activated the solid state switching device supplies voltage to illuminate the high LED indicator and a signal voltage to the heated seat module indicating the high mode is active. The second time the heated seat switch is activated the solid state switching device supplies voltage to illuminate the low LED indicator and a voltage signal to the heated seat module indicating the low mode is active. When the heated seat module receives a high or low mode active signal from the heated seat switch signal circuit, battery voltage is supplied to the seat cushion and back heater elements. The heated seat cushion thermistor provides a signal to the heated seat module used to determine the seat cushion temperature. The heated seat module regulates the supply voltage to the heater elements according to the inputs from the heated seat switch and the seat cushion thermistor.