Heating Characteristics

WARNING: This page is about a different car, the 2009 Mercury Milan, 2009 Lincoln MKZ, and 2009 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: The presence of overtemperature faults (DTCs B2729, B2730, B272A and B272B) can be induced by incorrect operation of the climate controlled seat system after an initial HEAT setting has been attained. If a HEAT setting is repeatedly turned OFF and ON in an attempt to increase the seat temperature, an overtemperature condition can result and the DTCs will be set.

In HEAT mode, the TED circuits of a given seat are wired in parallel internally in the DCSM.
The climate controlled seat system draws approximately 24 amperes, with both seats heating, until reaching the set point and then the system operates at a reduced amperage to maintain the climate setting.
In HEAT mode, the TED can add up to 40°C-60°C (72°F-108°F) to the ambient air temperature entering the system.
There are 3 manual settings based on the LEDs above each seat heat switch button on the HVAC module. The first setting is HIGH (3 LEDs), the second setting is MED (2 LEDs), the third is LOW (1 LED) then OFF (no LEDs).
In the LOW setting, the DCSM is set to maintain TED temperature at approximately 46°C (115°F).
In the HIGH setting, the DCSM is set to maintain TED temperature at 65°C (149°F).
When heating, the DCSM will vary the speed of the fans and the TED duty cycle in order to reach and maintain the temperature determined by the switch setting.
Seat heating has a maximum operating duration of 15 minutes.

Climate Controlled Seat Heat State	Initial Temperature	Final Temperature
HIGH	90°C (194°F)	65°C (149°F)
MED	80°C (176°F)	60°C (140°F)
LOW	75°C (167°F)	46°C (115°F)