HVAC Module
WARNING: This page is about a different car, the 2020 Ford Transit Connect. However, it is still accessible from the selected car via links, so may be relevant.
The heated seat control switches are part of the HVAC module. The HVAC module monitors the seat cushion temperature sensor and supplies heater current to the seat cushion and backrest heater mats until the desired setpoint temperature is reached. Once the setpoint temperature is reached, the HVAC module cycles the heater circuits on/off as required to maintain the setpoint temperature. PMI is required if installing a new HVAC module.