Controlling the Climate In the Passenger Compartment
Controlling the climate in the passenger compartment
Controlling the climate in the passenger compartment
For Climate control module (CCM) for ECC it is possible to use either manual settings or the AUTO function. In the latter case the control module automatically regulates heat, air conditioning, recirculation and air distribution until the selected temperature is achieved.
For Climate control module (CCM) for ETC it is only possible to use manual settings for damper position and fan speed. The control module automatically regulates heat according to the preset position so that selected temperature is achieved.
Climate control module (CCM) (4/6) regulates the following:
- Activation of the air conditioning (A/C) compressor (8/3) using a request via the controller area network (CAN) to the engine control module (ECM) (4/46)
- Controlling the damper motors, (6/48), (6/95), (6/96) (only ECC), (6/102) (only ECC) and (6/103).
- Speed of blower fan (6/28) via pulse width modulation (PWM) signal, directly connected.
The climate control module (CCM) regulates the climate in the passenger compartment based on the following input signals:
- Passenger compartment temperature, signal from the passenger compartment temperature sensor (7/10).
- Outside temperature, signal from the outside temperature sensor (6/62) via the engine control module (ECM) on the controller area network (CAN).
- Humidity sensor (7/90) (only EEC)
- The evaporator temperature, signal from the evaporator temperature sensor (7/41)
- Sun roof status, signal from the sun roof module (SRM) (4/33) via the central electronic module (CEM) over the controller area network (CAN).
- Status of the side window, signals from the driver door module (DDM) (3/126) and passenger door module (PDM) (3/127) via the controller area network (CAN)
- Status of the doors, signal from the central electronic module (CEM) via the controller area network (CAN)
- The sun intensity, signal from sun sensor (7/12) via the central electronic module (CEM). After structure week 200746, there are 2 signals, one for the right-hand side and one for the left-hand side.
- Speed, signal from the brake control module (BCM) (4/16) via the controller area network (CAN)
- Status of the windshield wipers, signal from the steering wheel module (SWM) (3/130) via the controller area network (CAN).
The climate control module (CCM) uses information about the status of the sun roof, side windows and doors to determine how it should compensate for changes in the passenger compartment temperature. If any side windows, doors or the sun roof are opened, the climate control module (CCM) will not compensate for a change in the passenger compartment temperature. Instead it maintains the same level of climate control for the compressor and blower fan (only ECC) as before.
The climate control module (CCM) (for ECC) uses the signal from the steering wheel module (SWM), indicating that the windshield wipers are on. This is to regulate the blower fan and the damper motor to remove any mist from the inside of the windshield when it rains.
For vehicles manufactured before structure week 200745, the following applies:
The climate control module (CCM) uses the signal from the sun sensor to compensate for high sun intensity. This is done by lowering the temperature of the ventilation air and for ECC, altering air distribution and increasing the speed of the blower fan.
For vehicles manufactured after structure week 200746, the following applies:
The Climate control module (CCM) for ECC registers the sun intensity on the left and right sides. Using these signals, the Climate control module (CCM) compensates for the high sun intensity.
This is done by reducing the temperature of the ventilation air on the affected side. The distribution of air is altered and the speed of the passenger compartment fan is increased.
The climate control module (CCM) uses the signal from the evaporator temperature sensor to control the activation of the air conditioning (A/C) compressor. If the signal from the evaporator temperature sensor indicates an evaporator temperature below 2-3°C, the compressor is not permitted to start because of the risk of freezing.
To maintain a constant flow of air in the passenger compartment, the climate control module (CCM) uses the speed signal from the brake control module (BCM) to regulate the speed of the blower fan. Generally, as the speed of the car increases the speed of the blower fan decreases.
At higher speeds the flow of air into the fresh air damper is adjusted.
When adjusting the climate settings manually, such as setting the temperature, this is displayed on the Infotainment control module (ICM). The climate control module (CCM) transmits a signal to the Infotainment control module (ICM) (3/281) via the controller area network (CAN).