Seating - Climate Controlled: Notes

Overview

The climate controlled seat system is able to heat and cool the front seats. Each climate controlled seat is operated by activating buttons on the FDIM (touchscreen interface). Each front seat temperature is then monitored and controlled by the DCSM located on the front passenger seat track.

The dual climate controlled seat system contains the following components:

FDIM (touchscreen)
DCSM
TED and blower assembly within each front seat cushion and backrest
air filter attached to each TED and blower assembly (for cushion TED, turn to the left to remove the filter) (backrest TED filter is not serviceable)
cushion TED adapter attached to the cushion frame
cushion and backrest manifolds
cushion and backrest foam pads
cushion and backrest trim covers

Remote Start Climate Operation (if equipped)

The customer can select different climate control modes/preferences when the vehicle is started using the remote start feature. This can be accessed through the message center. For additional information on how to set the remote start preferences, refer to the Owner's Literature. When the driver seat and/or passenger seat is set to AUTO mode, the driver/passenger heated/climate controlled seat activates in full heat mode when the outside temperature is less than 0 ° C (32 ° F) and full cool mode (climate controlled seats only) when outside temperature is greater than 26.7 ° C (80 ° F) any time the vehicle is started using the remote start feature. No heated/climate controlled seat adjustments are recognized during remote start operation. Once the ignition is cycled to the ON position, the heated/climate controlled seat returns to the previous settings (last ignition ON cycle) and adjustments can be made normally. If the previous setting was off, the heated/climate controlled seat turns off.

System Operation

System Diagram

Courtesy of FORD MOTOR COMPANY

Network Message Chart

Broadcast Message	Originating Module	Message Purpose
Climate control touchscreen and voice requests	APIM	The climate control requests message contains the climate controlled seat system request information. When any climate controlled seat function is requested using the FDIM (touchscreen), this input is used to activate the climate controlled seat system.

Broadcast Message	Originating Module	Message Purpose
Climate controlled seat set status	DCSM	The climate controlled seat set status message provides the current status of the climate controlled seats to the APIM. The APIM then updates the displayed status of the climate controlled seat buttons on the FDIM (touchscreen).

When the climate control seat buttons are activated on the touchscreen interface, the APIM sends the climate controlled seat commands to the FCIM using the I-CAN. The FCIM sends the request message to the IPC using the I-CAN. The IPC sends the request message to the BCM over the HS-CAN. Finally, the BCM sends the climate controlled seat commands to the DCSM using the MS-CAN.

Climate Controlled Seat System

The seat cushion is equipped with a TED assembly that includes a seat blower (fan motor, serviced as an assembly with the TED). Similarly, the seat backrest is also equipped with its own TED assembly with blower. Cabin air is drawn through the blower and distributed to each TED located in the seat cushion and backrest. The TEDs heat or cool the air, which is then directed into the foam pad and manifold where it is distributed along the surface of the cushion and backrest of the seat. Once the system is activated, the DCSM uses a set of flexible algorithms to control the heating/cooling modes and the blower speed dependant on the commanded climate controlled seat settings.

The DCSM monitors seat cushion temperature while it supplies voltage and ground to both blower motors. The DCSM also supplies a variable voltage signal to control the blower speed. Cabin air enters the blower through a filter attached to the TED housing. Heated or cooled air exits the TED and flows through a manifold attached to the foam pad.

Climate Controlled Seat Heating Characteristics

In heat mode, the TED can add up to 40-60 ° C (72-108 ° F) to the ambient inlet air temperature as it passes over the TED.
The system control settings are indicated next to each climate controlled seat heat switch button on the touchscreen. The first setting is HIGH (3 indicators), the second setting is MED (2 indicators) and the third is LOW (1 indicator) then OFF (no indicators).
When heating, the DCSM varies the speed of the blowers and the TED duty cycle in order to reach and maintain the desired temperature determined by the switch setting.

Climate Controlled Seat Cooling Characteristics

In cool mode, the TED can remove up to 8 ° C (14 ° F) from the ambient air temperature entering the system.
The system control settings are based on the 3 indicators next to each climate controlled seat cool switch button on the touchscreen. The first setting is HIGH (3 indicators), the second setting is MED (2 indicators) and the third is LOW (1 indicator) then OFF (no indicators).
When cooling, the DCSM maintains constant speed of the blowers and constant TED supply voltage (duty cycle is determined by the switch setting) in COOL mode.

Climate Controlled Seat Recovery Mode

NOTE: The presence of overtemperature faults (DTCs B2729, B2730, B272A and B272B) can be induced by incorrectly operating 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 or repeatedly toggled between heat and cool modes, an overtemperature condition can result and the DTCs may be set.

If the temperature at one of the TEDs rises above 110 ° C (229.8 ° F) in the heat mode or 65 ° C (148.9 ° F) in the cool mode for more than 4 seconds, the DCSM records an overtemperature DTC, removes voltage from the TEDs and goes into recovery mode (blower only) for 30 seconds to cool down the TEDs. The same occurs if a temperature difference of 60 ° C (108 ° F) or greater is seen between the backrest and cushion TEDs on either front seat. The DCSM continues to monitor the TEDs while in recovery mode. If the temperature of the TEDs does not drop to 105 ° C (220.8 ° F) in the heat mode or 60 ° C (139.9 ° F) in the cool mode after 30 seconds, the system continues to cool the TEDs in recovery mode for up to 5 minutes. If the TEDs cool down after 30 seconds, but before 5 minutes (checked at 4 second intervals), the system operates as normal. An overtemperature DTC is still recorded even if the system recovers and is operating normally. This is more likely to occur during extreme cabin temperatures with significant seat back sun load. If the system does not recover within 30 seconds in heat mode or within 5 minutes in cool mode, the DCSM disables that seat (fault mode) and remains off until the ignition is cycled. Also, if the DCSM detects temperature differential fault twice during the same ignition cycle, the DCSM disables the seat. When a fault causes a shutdown, the climate controlled seat indicators turn off and that seat is not operational until the next key cycle.