194001899 - AIR CONDITIONING CASING AND COMPONENTS
AIR CONDITIONING CASING
The air conditioning casing, in other words the plastic structure fastened to the dashboard supporting crossmember, is the same on both the manual and the automatic version.The difference between the manual and automatic versions (as far as the air conditioning casing is concerned) lies exclusively in the type of mixture, distribution and recirculation flap movement actuators.COMPONENTS
The components for the type of system are listed in the table below.| Components | MANUAL climate control | AUTOMATIC climate control |
|---|---|---|
| DC actuators | X | X |
| Stepping actuators | X | |
| Mixed air temperature sensors | X | |
| Heater radiator | X | X |
| Evaporator | X | X |
| Expansion valve | X | X |
| Fan | X | X |
| Climate control node | X | X |
| Compressor | X | X |
| Condenser | X | X |
| Linear sensor | X | X |
| Outside air temperature sensor | X | |
| Passenger compartment air temperature sensor | X | |
| Solar sensor | X | |
| Pollen filter | X | X |
| Drier filter | X | X |
| Air quality sensor (AQS) | X |
Description of the components
The location of the main components is illustrated in the diagram below
ACTUATORS
The movement of the flaps inside the climate control casing, in other words the air mixing, distribution and recirculation flaps, takes place thanks to electro-mechanical actuators controlled by the NCL.On the manual climate control versions, the actuators contain a motor with a 12 volt power supply that controls the rotary movement of a drive pin, by means of linkage, acting directly on the flaps. On the mixing and distribution actuators a potentiometer determines the effective position of the flap and acts as feedback for the control unit. The recirculation actuator does not require a potentiometer.The actuator for the manual version is illustrated in the diagram below.
Air distribution actuator
The air distribution actuator operates the rotation of the distribution flaps by moving a cam that acts on an idler linkage for each flap.On the manual climate control version it receives a 12 volt power supply and, by reversing the polarity, it can be made to rotate either clockwise or anti-clockwise. A potentiometer measures the effective position and acts as feedback for the control unit, checking the complete travel between the end of travel positions. It is fitted on the climate control casing on the right hand side.On the automatic climate control version the actuator is replaced by a stepping motor. As the automatic version is the dual zone type, the mechanism that moves the flaps is on both the left and right sides of the climate control system. The movement of the flaps for the left and right sides is completely independent of one another. The positioning takes place by counting the number of steps required to reach the position.Air mixing acuator
This actuator activates the rotation of the air mixing flaps by means of linkage. It is fitted on the climate control casing on the pasenger side.On the manual climate control version it receives a 12 volt power supply and, by reversing the polarity, it can be made to rotate either clockwise or anti-clockwise. A potentiometer measures the effective position and acts as feedback for the control unit, checking the complete travel between the end of travel positions.It is fitted on the climate control casing on the left side.On the automatic climate control version the actuator is replaced by a stepping motor. As the automatic version is the dual zone type, the mechanism that moves the flaps is on both the left and right sides of the climate control system. The movement of the flaps for the left and right sides is completely independent of one another. The positioning takes place by counting the number of steps required to reach the position.Recirculation actuator
The actuator manages the rotation of the flap in two extreme positions: dynamic (outside) air and recirculation, without intermediate positions.It is fitted in the area of the dynamic air intakeIt receives a 12 volt power supply and, by reversing the polarity, it can be made to rotate either clockwise or anti-clockwise.CLIMATE CONTROL SENSORS
Mixed air temperature sensors
There are four temperature sensors on the automatic climate control casing that provide the climate control system control unit with a signal relating to the temperature of the air coming out of the vents. Two sensors are located by the FLOOR outlets and two others by the dashboard side vent outlets.The sensors are the NTC type and feature a resistance of 10000 Ohm +/- 3% at a temperature of 25 °CThe temperature sensor is illustrated in the diagram below.
Solar sensor
The solar sensor is located on the top part of the dashboard at the base of the windscreen.Its task is to transform the light signals (lux or kcal/m²h) into a corresponding linear electrical signal to supply a value proportional to the thermal energy introduced into the passenger compartment through the windscreen through the effect of the sun''s rays.This sensor is only fitted on the automatic climate control version.The sensor is a special type of diode (photodiode) which can alter its conduction depending on the quantity of light coming into contact with it.If the climate control system control unit (NCL) is managing the system in AUTO mode, it uses this signal and alters the air temperature and distribution parameters to maintain the temperature requested by the user.
Pollution sensor (aqs)
The AQS sensor is an electronic device that is designed to send an opening/closing signal signal to the distributor unit recirculation flap when the outside air pollution index exceeds pre-set harmful levels to prevent polluted air from being introduced into the passenger compartment.It is installed in the distributor unit outside air intake.It is possible, through the use of a special sensitive element, to detect the presence, in the air surrounding the vehicle, of oxidizing pollutant particles (e.g. CO) or reducing agents (NOx).The sensitivity of the system is improved by the potential danger of the pollutant gases according to the M.A.K. index (Maximal Concentration of Harmful Substances at Work Over 8 Hours).The sensitive element is heated and regulated at a constant temperature of 300°C to supply the same performance in an ambient temperature range of between -40 and +85°C. It is not affected by the speed or the temperature of the air passing through it.The AQS sensor is illustrated in the diagram below.
| PIN | FUNCTION |
|---|---|
| 1 | Power supply +15 (INT) |
| 2 | Reference earth from NCL |
| 3 | PWM signal for NCL |
| PWM signal | Description of the signal |
|---|---|
| 0% | Short circuit to earth of the signal line |
| 20% | Non polluted air circulation |
| 20% | Level 1 pollution |
| 50% | Level 2 pollution |
| 60% | Level 3 pollution |
| 80% | Sensor error |
| 100% | Short circuit to +12V signal line |
| Time not in use | Response time |
|---|---|
| < 24 h | max 1 sec |
| 24 h < t < 76 h | max 30 sec |
| 76 h < t < 480 h | max 180 sec |
| > 480 h | max 300 sec |
Outside air temperature sensor
It is an NTC sensor fitted on the bottom of the left door mirror (right on right hand drive versions).It is only fitted on versions with automatic climate control.It supplies a signal proportional to the temperature of the outside air.It is connected to the driver''s door control unit (NPG) which transmits the outside temperature signal via the CAN. The value transmitted via the CAN is always expressed in degrees °C.The outside temperature should be measured with an accuracy of at least 0.5°C and with a tolerance of +/- 5%, including the tolerance of the sensor and the acquisition hardware.The NCL uses this signal for the automatic control strategies.If the data is missing or is not valid, the NCL uses the last valid figures and, after a period that can be adjusted, assumes a default value (which too can be adjusted in the EEPROM).Depending on the outside temperature, the NQS warns the user of possible "ice danger" by means of a symbol and specific message.The NQS only displays the outside temperature in °C.The same is also valid for the NIT (Connect Nav+) if fitted.To sum up, the sensor sends the outside temperature signal to the NPG which forwards it, via the B-CAN, to the NCL, the NQS and the NIT (if fitted) and to the Body Computer NBC. The latter, by means of the outside temperature signal gateway (from the B-CAN to the C-CAN), sends the signal to the NCM which gives the go ahead for the activation/deactivation of the compressor.Passenger compartment air temperature sensor
This NTC type sensor has the task of notifying the climate control system management control unit of the temperature of the passenger compartment making the system able to correct the climate control parameters in order to respect the temperature set by the user.This sensor is only fitted on versions with automatic climate control.It is incorporated in the climate control system control unit and has a fan designed to prevent the build up of air inside it and make the temperature reading as consistent as possible.EXPANSION VALVE
The tasks of this valve are to:- Separate the high pressure circuit from the low pressure circuit;- Expand the refrigerant (change in state from liquid to gas);- Regulate the evaporation process (flow rate);- Regulate the evaporation temperature;- Protect the compressor from refrigerant fluid.The thermostatic expansion valve is fitted on the evaporator inlet and outlet ducts with the task of regulating the flow and expansion (drop in pressure) of the R134a fluid before entry into the evaporator.The automatic regulation of the size of the passage for the gas inside the expansion valve is produced by a sensitive bulb which measures the temperature of the refrigerant fluid and depending on this suitably adjusts the size of the opening that the gas passes through by means of a special spri| ... DATA ERROR - CROPPED TEXT | Ошибка данных - Текст обрезан ... |
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