Mini Cooper temperature gauge goes to red zone, fan comes on

check your heater core and your thermostat. your thermostat first.

check coolant level could be too low allowing air in the cooling system causing air pocket in engine around the engine coolant sensor.coolant sensor needs to be in hot coolant so it will cause the cooling fan to come on at a set temperature.make sure coolant correct level and the coolant level in the cooling overflow jug should be at full cold mark.the cooling overflow jug should never be empty,if you see empty cooling overflow jug air got in the cooling system so make sure when engine cold every time raise hood make sure cooling overflow jug coolant level at full cold mark.if jug stay empty you have cooling leak.so replace radiator cap,if coolant level all good,i would replace the engine coolant temperature and thermostat.when your car come to a long stop or driving along long line of slow moving traffic the engine coolant blower motor should running if not have vechicle code scan for faulty coolant fan motor control module.or ecm problems.

Low oil no. Low water yes simply check the water. I don't think the temperature sensor is bad. The problem is probably due to the car running hotter.

THIS IS THE CHECK ENGINE LIGHT, HAVE A KRAGEN OR AUTOZONE PARTS STORE TEST THE OBD2 ELECTRONIC ENGINE CONTROL SYSTEM FOR THE FAULT CODE THAT IS STORED WHEN THIS LIGHT COMES ON,.

hi it sounds like the engines electric cooling fan has automatically come on as the engine has got hot enough for it to be cooled down
you may have never noticed it before .
check your coolant level and your oil level to be on the safe side and keep an eye on the temperature gauge the fan should come on when the gauge goes past normal running teperature if its coming on a lot there may be a problem but its probably working as normal

Bad head gasket or cracked head

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the fan comes on and off based on the "temperature sending unit" thats a thermal switch mounted on the radiator .. it is normal for the temperature to fluxuate as the fan turns on and off .. if it is allowed to get too hot before turning on then the temperature sending unit should be replaced ...while the car is moving the fan may never come on and isnt needed as long as air is flowing through the radiator .. as long as you are not loosing coolant then the temperatures are probably within proper range ... a sticking thermostat can also cause increased temperature range fluxuations .. that will show up as large swings of temp while driving .....

check your oil and coolant level to be on the safe side but it sounds like everything is normal if there is no airflow across the radiator the fan will operate when the engine gets hot even with the engine off

I had this exact same problem -- for about a year and a half! Replaced thermostat, replaced sensor twice, replaced overflow tank, replaced radiator cap, placed a grounding kit on the car in case the problem was electrical ... and was ABOUT to replace thermostat again and then the water pump when a new mechanic suggested we bleed air out of the cooling system. The heater core was PACKED with air, as was the upper hose valve area. Previous mechanic had been using a pressurized fill device to bleed the system and this had just been backing air into the heater core. There are two valves under the hood for bleeding air -- one on the heater core and one on the upper hose. It only takes a few minutes to fix this!

please replace the thermostat