Heated Seats - Front

WARNING: This page is about a different car, the 2012 Ford Pickup. However, it is still accessible from the selected car via links, so may be relevant.

The heated seat system operates independently from the climate control system and is controlled by the heated seat module located underneath the front passenger seat cushion.

On vehicles equipped with a navigation system, the heated seat buttons are part of the Front Controls Interface Module (FCIM) controls. When a heated seat button on the FCIM is pressed, a request message is delivered via MS-CAN communication to the HVAC module. The HVAC module then provides a momentary ground to the heated seat module to command the system on or off.

On vehicles not equipped with a navigation system, the heated seat buttons are part of the HVAC module. When a heated seat button on the HVAC module is pressed, the HVAC module provides a momentary ground to the heated seat module to command the system on or off.

The heated seat module supplies voltage to heater mats located in the seat cushion and backrest to heat the seat. The heated seat module monitors a temperature sensor in each cushion heater mat and regulates the seat temperature. The heated seat module is designed to remain on, heating the seat and maintaining temperature until switched off.

Normal heat cycle may require several minutes to initially warm the seat. The seat should be occupied to correctly test for normal operation. Temperature measuring devices do not provide an accurate method for testing heated seat operation as surface temperatures are subject to human and environmental characteristics. Correct testing requires heater mat resistance measurements which have tight tolerances affecting the length of time for the heater mats to reach maximum operating temperature.

The heated seat module monitors the heater output and thermistor circuits for fault detection but does not report DTCs and is not connected to the communication bus circuits. If an open circuit or short to ground occurs, the output is disabled to the heater mats and the heated seat indicators turn off. When a fault is detected, the heated seat module only disables the affected seat and the other seat may continue to operate normally. The heated seat cannot be operated until the system is repaired and the ignition is cycled OFF and ON to reset the heated seat module from the detected fault.

The HVAC module monitors the control circuits to the heated seat module and will set a DTC if a circuit fault is detected. Refer to the DTC Charts .

The heated seat module is used on 2 different heated seat systems, front heated seat only or front and rear heated seats. These systems use 2 different on/off switches, a single momentary switch and a dual momentary switch. A new heated seat module is programmed to function for a single momentary switch system and is designed with an auto-configuration feature. If a new module is installed in a dual momentary switch system, the auto-configuration feature sets the operating characteristics of the module the first time a heated seat button is pressed. Once the module is configured for a dual momentary switch system it does not function correctly in a single momentary switch system unless the module is reset. Refer to HEATED SEAT MODULE RESET .

If the module has been auto-configured for a dual momentary switch system and is then installed in a single momentary switch system, the front heated seats displays both a symptom of operating only in one mode and illuminating only one indicator. If this condition exists, a reset procedure is required to correctly configure the heated seat module for use. For diagnosis of this condition, GO to SYMPTOM CHART .