Hi mate , I have just had the same problem , no warning signs or lights until I started my car this morning and a warning flashed up to turn off the engine and check coolant level. When I checked the level was almost empty so I’ve topped it up with water to see if I have a leak ( nothing as of yet ) but when I put the heating on it’s working fine on the passenger side but Luke warm on the drivers side , I haven’t had the system pressure tested yet but I’m hoping I don’t need the heater matrix replaced as I have been quoted around £350 just to strip the dash out and I am dreading to see the price after the part and installation, is that a requirement to strip the whole dash to get to the heater matrix??
