Heater/Air conditioningHeater/Air conditioning  - For pleasant driving - Mitsubishi ASX Owner's Manual - Mitsubishi ASX

The heater/air conditioning can only be used while the engine is running.

See also:

Manual air conditioning
The air conditioning can only be used while the engine is running. ...

Air conditioning system refrigerant and lubricant recommendations
If the air conditioning seems less effective than usual, the cause might be a refrigerant leak. Have the system inspected by your authorized MITSUBISHI dealer. The air conditioning system in your v ...

Information screen (when the ignition switch is turned from “OFF” to “ON”)
When the ignition switch is turned to the “ON” position, the display screen switches in the following order. 1- Screen when the ignition switch is “OFF” 2- System check screen 3- Screen ...