Circuit/System Description

The driver and passenger seat heating elements are controlled by a common high current relay internal to the heated seat module and by individual low side element control circuits. The heated seat module connects the heated seat heater element supply voltage circuits for both seats to a common reference point. This reference point is biased to approximately 2.0 volts. Before the heated seat module will allow heated seat operation, it checks to see if this reference voltage is shorted to ground or voltage. Once the module verifies that it is not closing to a shorted heating element, it allows for heated seat operation. The module will then continue to monitor the heating elements for a shorted circuit.