2019 2.4 heater fail

Hi all, I have a 2019 2.4 and the heater failed this morning, just blowing cold air no matter what setting I try. It was in for service December and when it came back I could hear a slight noise from the heater fan which was not there before. 2 months later, only blowing cold air and I don't hear the noise anymore. Any ideas before I book it in again with a 60 mile round trip to the nearest dealer.

Nobody had this before? Its a strange one. Checked the coolant, all ok. No heat from either the electric pre heat using the app or running the engine in charge or save mode. Just blows cold air no matter what....

Plenty of vehicles have had heating problems before, search the forum and you'll plenty of information around why. But most of them are related to the 2.0 engine and sand left in the engine block from the casting process.

There are 2 basic things to check - the electric water pump and the 4 port valve.

Thanks littlescrote.

I rang the mitsubishi garage (jct600) to book the car in under warranty. I was informed on the phone that the heater failure is not a warranty item! Obviously we are going to have issues. After reading other issues and watching a few videos I am thinking the thermostat has gunged up on the 4 way heater valve port. This may be caused by the service agent using incorrect coolant apparently. I have to wait 3 weeks before they have a slot at my nearest quasi dealer 30 miles away. Its been near freezing the last few days and even with the heated steering wheel and seat its not comfortable.