Outside is 15 Celsius, but A/C shows outside temp is minus 40Celsius? Last winter, outside temp is about minus 35Celsius, then A/C shows outside temp is about zero?

I am guessing this is an outside weather temperature thing? Have you checked the batteries of the outside probe? Made sure the "channel" is on the right setting etc?

Need a new ambient air temp sensor

check near front bumper for a tiny black sensor somewhere near number plate the sensor seems loose or bad connection on wire ,not 100% sure where sensor sits but pretty sure its a bad connection on plug to sensor as it is a common prob on bmw when sensor loose /bad connection show minus 40deg when its hot outside and display plays up vw polos have same prob

Have u got the answer?

Could be just the heat off the hot radiator in a minus temp environment. Just like your breath outside on a cold morning?

However if you doubt that is the case then try to see where exactly the smoke is coming from (Mind not to burn yourself). Maybe a leaking Rad hose/cap?

Hope this helps

I would imagine that the car is fitted with some sort of menu where you can change the vehicle's readout settings into metric, so that now your car is reading in kilometers per hour and is also displaying temperature in the metric range.
You should access any in vehicle computer and reselect the ranges you wish to use.

Have you checked the coolant temp sensor to see what the resistance is or to see if it is unplugged?

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

Had the same problem, replaced the ambient air temp sensor in front of the radiator. Cost is like 10-15 bucks. Don't worry if temp doesn't change right away. Took me about 5 miles and then it worked great.

the temp display can be switched between celsius and farenheit readings, since the car is from europe the default is celsius, The manual has instructions on changing back, You have to hold 2 buttons on the display per the manual.

venkovní senzor teploty vzduchu v p?edním nárazníku je vadné! Klimatizace se nikdy nespustí kdy? je teplota venku ni?ší ne? 7. stupe? Celsius. Auto má údaj ?e je venku zima,tak proto A/C nefunguje. Vym?nit senzor a bude to O.K.