Air intake control
Single zone system with manual control
The air source is controlled manually by pressing the fresh/recirculating air switch located on the control panel. When the switch is pressed, the ATC module turns on the LED in the switch and closes the air intake damper. Pressing the switch a second time causes the ATC module to turn off the LED in the switch and open the air intake damper, allowing fresh air to enter the passenger compartment.
NOTE: The ATC module reduces the amount of fresh air entering the passenger compartment to reduce the effect of ram air caused by the vehicle moving forward.
When air recirculation mode is selected, the ATC module will return the air intake damper to the open position after a 3-minute period. This helps prevent fogging in the cabin. The 3 minute air recirculation time interval can be canceled by pressing and holding the fresh/recirculating air switch until the switch flashes three times. The air intake damper will now remain closed until the next driving cycle.
The ATC module controls the position of the air intake damper by providing LIN bus messages to the air intake damper stepper motor. The Hall sensor located in the stepper motor informs the ATC module that the stepper motor is moving.
Dual zone automatic system
The air source is controlled automatically unless overridden by pressing the fresh/recirculating air switch located on the control panel. In automatic control, the ATC module determines the desired position of the air intake damper using its algorithm "comfort", based on the input signals from the outside temperature sensor and the interior temperature sensor.
When the car enters power mode 6 for the first time (ignition on), the LED indicator on the fresh/recirculated air switch lights up and the air intake source is automatically controlled by the ATC module. The ATC module will control the air intake source according to the outside temperature and the desired interior temperature. The air intake damper will open allowing fresh air to enter the cabin, although a small amount of recirculated air will also be present.
NOTE: The ATC module reduces the amount of fresh air entering the passenger compartment to reduce the effect of ram air caused by the vehicle moving forward.
Pressing the fresh/recirculating air switch once will turn off the indicator. The ATC module now closes the air intake damper and allows only recirculated air to enter the passenger compartment for a 3-minute period. After this period, the ATC module returns the air intake damper to automatic control. This helps prevent fogging in the cabin.
Pressing the fresh/recirculated air switch a second time also returns the air intake source to automatic control and turns on the indicator light.
The 3 minute air recirculation time interval can be canceled by pressing and holding the fresh/recirculating air switch until the switch flashes three times. The air intake damper will now remain closed until the next driving cycle.
The ATC module controls the position of the air intake damper by providing LIN bus messages to the air intake damper stepper motor. The Hall sensor located in the stepper motor informs the ATC module that the stepper motor is moving.
Two-zone automatic system with contamination sensor
The air source is controlled automatically unless overridden by pressing the fresh/recirculating air switch located on the control panel. In automatic control, the ATC module determines the desired position of the air intake damper using its algorithm "comfort", based on inputs from the outside temperature sensor, interior temperature sensor, and pollution sensor.
NOTE: The ATC module reduces the amount of fresh air entering the passenger compartment to reduce the effect of ram air caused by the vehicle moving forward.
When the car enters power mode 6 for the first time (ignition on), the 'AUTO' LED on the fresh/recycled air switch lights up and the air intake source is automatically controlled by the ATC module. Pressing the fresh/recirculating air switch once will turn off the 'AUTO' indicator and turn on the 'MAN' indicator. The ATC module now closes the air intake damper and allows only recirculated air to enter the passenger compartment for a 3-minute period. After this period, the ATC module returns the air intake damper to automatic control. This helps prevent fogging in the cabin.
Pressing the fresh/recirculating air switch a second time will turn off both 'AUTO' and 'MAN' indicators. The ATC module will now control the air intake source according to the outside temperature and the desired interior temperature. The air intake damper will open allowing fresh air to enter the cabin, but a small amount of recirculated air will also be present. The amount of recirculated air is determined by the ATC module using its algorithm "comfort", based on the input signals from the outside temperature sensor and the interior temperature sensor.
A third press of the fresh/recycled air switch returns the air intake source to automatic control and turns on the 'AUTO' indicator.
The 3 minute air recirculation time interval can be canceled by pressing and holding the fresh/recirculating air switch until the switch flashes three times. The air intake damper will now remain closed until the next driving cycle.
The ATC module controls the position of the air intake damper by providing LIN bus messages to the air intake damper stepper motor. The Hall sensor located in the stepper motor informs the ATC module that the stepper motor is moving.
Air temperature control
Single zone system with manual control
The interior temperature is selected by turning the left knob to the required position. Turning the regulator counterclockwise reduces the temperature of the air leaving the heater; turning the knob clockwise raises the temperature of the air leaving the heater.
Maximum heating and cooling are represented on the control panel by red and blue dots respectively. When maximum heating or cooling is selected, the algorithm «comfort» in the ATC module adopts the appropriate strategy for air source, air distribution and fan speed to maintain maximum heating or cooling in the cabin.
The ATC module regulates the temperature of the air leaving the heater by changing the position of the temperature mixing damper. The temperature mixing damper directs part of the cooled air from the evaporator through the heater core to maintain the desired outlet temperature. The ATC module controls the position of the temperature mixing damper by providing LIN bus messages to the mixing damper stepper motor. The Hall sensor located in the stepper motor informs the ATC module that the stepper motor is moving.
Dual zone automatic system
Two-zone systems have two rotary heating controls that provide individual climate control for the left and right sides of the passenger compartment. The choice of temperature can be made by turning the knob according to the desired temperature marked on the control panel. Turning any knob past 16°C initiates the maximum cooling strategy; turning any knob above 28°C initiates the maximum heating strategy.
NOTE: Maximum cooling or heating can only be achieved if both rotary controls are set to the same position.
The ATC module is able to maintain a constant temperature on both sides of the cabin by monitoring the feedback from the cabin temperature sensor. Until any manual override is selected, the ATC module will automatically control the air intake source, cabin air distribution and fan speed to maintain the required temperatures.
Dual zone systems have two temperature mixing dampers that provide individual temperature control for the left and right sides of the passenger compartment.
NOTE: The temperature setting for the driver's side has priority over the temperature setting for the passenger's side.
Temperature mixing dampers are installed on the left side of the heater and direct some of the cooled air from the evaporator through the heater core to maintain the desired outlet temperature. The ATC module controls the position of the temperature mixing dampers by sending messages via the LIN bus to the mixing damper stepper motors. Hall sensors located in the stepper motors inform the ATC module that the stepper motors are moving.
Electric blower control
Single zone system with manual control
The blower fan speed is set by turning the right knob to the required position. The right rotary control allows you to select 14 fan speeds. Turning the knob fully counterclockwise turns off the electric fan.
The operation of the blower fan is controlled by the ATC module using the blower control module. The ATC module supplies the blower fan control module with pulse-width modulated (PWM) signal based on the selected fan speed. The fan motor control module interprets the PWM signal as fan speed and controls the voltage to the fan motor accordingly.
Dual zone automatic system
The blower fan speed is controlled automatically by the ATC module until manual operation is requested. Manual override of the electric fan speed can be done by turning the central rotary control to the required position. The rotary control allows manual selection of 7 fan speeds. Turning the knob fully counterclockwise turns off the electric fan. When manual override is made, the 'AUTO' indicator located in the center of the rotary control goes out.
NOTE: The central rotary control contains two LEDs. When the electric blower is under automatic control, the upper (round) Light-emitting diode. When the interior air distribution is under automatic control (see below), the lower (rectangular) Light-emitting diode.
The electric fan can be returned to automatic control by pressing the 'AUTO' switch located in the center of the rotary control. When automatically controlled, the ATC module changes the speed of the blower fan in accordance with its algorithm «comfort», to maintain the desired temperature in the cabin. The ATC module also changes the blower fan speed to compensate for the effect of ram air on the air intake created as the vehicle moves forward.
The operation of the blower fan is controlled by the ATC module using the blower control module. The ATC module provides the blower fan control module with a PWM signal based on the desired fan speed. The fan motor control module interprets the PWM signal as fan speed and controls the voltage to the fan motor accordingly.
Air distribution control
Single zone system with manual control
The distribution of air entering the passenger compartment can be adjusted by turning the central rotary control to the desired position. The ATC module adjusts the position of the air distribution damper to the desired position by sending messages on the LIN bus to the air distribution damper stepper motor. The Hall sensor located in the stepper motor informs the ATC module that the stepper motor is moving.
Dual zone automatic system
Cabin air distribution is controlled automatically by the ATC module until manual operation is requested. Manual override can be made by pressing the corresponding momentary air distribution switch on the control panel. When manual operation is requested, the 'AUTO' indicator located in the center of the blower motor rotary control will turn off.
NOTE: The central rotary control contains two LEDs. When the blower fan is under automatic control (see above), the upper (round) Light-emitting diode. When the air distribution in the passenger compartment is under automatic control, the lower (rectangular) Light-emitting diode.
Air distribution can be returned to automatic control by pressing the 'AUTO' switch located in the center of the blower motor rotary control. This will turn on the 'AUTO' indicator and allow the ATC module to control the air distribution according to its algorithm «comfort».
The air distribution is controlled by two air distribution dampers. The ATC module controls the position of the air distribution dampers by sending messages via the LIN bus to the damper stepper motors. Hall sensors located in the stepper motors inform the ATC module that the stepper motors are moving.
ECON
Single zone system with manual control
Pressing the momentary 'ECON' switch on the control panel turns off the A/C system. When selected, the ATC module also sends a high speed CAN·message to the ECM to request that the A/C compressor be turned off. The ECM shuts down the compressor by turning off the A/C compressor control relay located in the BJB. The indicator in the switch will turn on to alert occupants that the system is in 'ECON' mode.
When 'ECON' mode is selected, temperature control is still maintained but there is no intake air cooling. The minimum air temperature at the outlet of the system will correspond to the temperature of the outside air with the addition of heat collected in the air intake path.
A/C can be turned on again by pressing the 'ECON' switch again. This also causes the 'ECON' indicator to turn off.
Vehicles equipped with «Stop/Start» - starting from MY 2010
From MY 2010 the 'ECON' switch will be marked 'A/C'. This is to prevent confusion with the 'Eco' switch that controls the systems «Stop/Start» And «Gear shift sensor». For more information, see the chapter: Starting system (303-06C Starting system - 2.2L Duratorq - Td4, Vehicles built from 03/2009, Description and function).
Two-zone system with automatic control
Pressing the momentary 'ECON/OFF' switch on the control panel turns off the A/C system. When selected, the ATC module also sends a high speed CAN·message to the ECM to request that the A/C compressor be turned off. The ECM shuts down the compressor by turning off the A/C compressor control relay located in the BJB. The 'ECON' indicator in the switch will turn on to warn vehicle occupants that the system is in 'ECON' mode.
When 'ECON' mode is selected, temperature control is still maintained but there is no intake air cooling. The minimum air temperature at the outlet of the system will correspond to the temperature of the outside air with the addition of heat collected in the air intake path.
Pressing the 'ECON/OFF' switch again will turn off the 'ECON' indicator and turn on the 'OFF' indicator. In 'OFF' mode (Off) the ATC module sets the fan speed to 0. The air distribution in the passenger compartment will remain at the pre-selected setting. All LEDs on the control panel will turn off, although the night-time illumination will remain active.
NOTE: When in 'OFF' mode (Off) the heated seats, heated windshield and heated rear window are still available.
A third press of the 'ECON/OFF' switch returns the system to normal operation (A/C) and turns off the 'OFF' indicator. The system can be returned to automatic operation at any time by pressing the 'AUTO' switch located in the central rotary control (blower electric fan).
Vehicles equipped with «Stop/Start» - starting from MY 2010
From MY 2010 the 'ECON' switch will be marked 'A/C'. This is to prevent confusion with the 'Eco' switch that controls the systems «Stop/Start» And «Gear shift sensor». For more information, see the chapter: Starting system (303-06C Starting system - 2.2L Duratorq - Td4, Vehicles built from 03/2009, Description and function).
Programmed Deicing
The programmed de-icing feature is only available on vehicles equipped with dual zone heating, ventilation and A/C. The function is selected by pressing the 'PROG' momentary switch on the control panel. Once selected, the ATC module provides maximum windshield de-icing/fogging by configuring the system as follows:
- 'AUTO' mode off
- Setting the air intake to fresh air
- Setting the air distribution to the air supply to the windshield
- Setting the blower fan speed to maximum
- Heated windshield on
- Rear window heating on
When programmable deicing is selected, the set temperature will remain unchanged. Programmable de-icing can be canceled by any of the following methods:
- Pressing any momentary air distribution switch
- Pressing the 'AUTO' switch located in the center of the electric blower rotary control
- Pressing the 'PROG' momentary switch a second time
NOTE: The blower fan speed can be adjusted manually without disabling the programmable deicing function.
Heated windshield
The heated windshield function includes two heating elements, left and right, glued between the layers of glass. The system is turned on by pressing the momentary switch located on the control panel. Once selected, the ATC module sends a heating request on the high speed CAN bus to the CJB. Upon receipt of the message, the CJB energizes the heated windshield relay located in the BJB, providing ground to the relay coil. The energized relay supplies battery voltage to both heating elements. After 4 minutes, the ATC module cancels the heated windshield request. The CJB then disables the heated windshield by clearing the relay coil ground.
The ATC module requests the operation of the heated windshield only when the engine is running. The engine status signal is supplied to the ATC module from the ECM via the high speed CAN bus.
Rear window heating
The rear window heating function includes one heating element glued to the inner surface of the glass. The system is turned on by pressing the momentary switch located on the control panel. Once selected, the ATC module sends a heating request on the high speed CAN bus to the CJB. Upon receipt of the message, the CJB energizes the heated rear window relay located in the auxiliary electrical junction box (AJB), to ground the relay coil. The energized relay provides battery voltage to the heating element. After 12 minutes, the ATC module removes the heating request. The CJB then disables the heated rear window by clearing the relay coil ground.
The ATC module requests the operation of the heated rear window only when the engine is running. The engine status signal is supplied to the ATC module from the ECM via the high speed CAN bus.
Heated exterior mirrors
The operation of the heated exterior mirrors is fully automatic and does not require any command from the driver. Heated exterior mirrors are active when the outside temperature is below 5°C and the engine coolant temperature is below 65°C. The ambient air temperature and engine coolant temperature are supplied from the ECM via the high speed CAN bus. Based on these temperatures, the CJB determines if heated exterior mirrors are required.
The CJB requests the heated door mirrors by sending a high speed CAN·message to the driver and passenger door modules. The door modules provide power and ground to the heating elements of the respective exterior mirrors. When the outside temperature and engine coolant temperature rise above the previously set values, the CJB sends an appropriate message on the high speed CAN bus to the door modules, canceling the heat request.
Seat heating
The operation of the seat heating system is controlled by the ATC module upon receipt of a heating request from one of the momentary seat heating switches located on the control panel. The switches are located in the left and right rotary controls. A single press of the seat heating switch initiates low level heating and illuminates the warning light. Pressing the switch a second time initiates high level heating and turns on the two pilot lamps. A third press turns off the seat heating.
Seat heating requests from the ATC module are sent via the LIN bus to the seat heating control modules. Each of the two seat heating control modules is installed under the respective front seat. The seat heating control modules provide power to the seat heating elements and the temperature sensors located in the seat cushion.
The seat heating control module provides a 5 V reference to the seat heating function temperature sensor. The seat heating function temperature sensor is an NTC thermistor. By monitoring the feedback voltage, the control module can calculate the seat temperature. If the temperature rises above the set temperature, the control module turns off the heating elements.
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