Function of auto recirculation
At outside temperatures of > 26 °C, following an initial system ventilation time of 30 seconds, the program switches to recirculation mode in order to accelerate the cooling phase.
Control of the air-conditioning compressor
Activation of the air-conditioning compressor depends on the outside temperature, intake air temperature and coolant temperature.
Activation: - Outside temperature > 5 °C
- Coolant temperature < 115 °C
- Ignition on
The air-conditioning compressor is switched on 7 seconds after the engine is started, at the earliest.
Switch-on conditions for coolant or condenser blower motors
Stage 1 is switched on when the coolant temperature is > 100 °C
there is an A/C demand, the intake air temperature is > 8 °C and terminal 15 is switched on.
Stage 2 is switched on when the coolant temperature is > 105 °C
the refrigerant pressure is > 16 bar.
Switch-on conditions for engine compartment fan
The engine compartment fan is switched on when the engine compartment temperature is > 80 °C
the coolant temperature is > 102 °C.
If the ignition is switched off and the engine compartment temperature is more than 60 °C, the DME control module remains in readiness for another 20 minutes. During this time, the engine compartment temperature is retrieved every 10 seconds. If the engine compartment temperature is > 85 °C, the engine compartment fan is switched on for 20 seconds. If the engine compartment temperature is still > 85 °C after this time, the fan remains on for a further 30 seconds.
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