General information

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.

After-running of engine compartment fan

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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