Over heating and blowing cold air

turn the temperature up to the hot to blend the hotter temperature

here is a link to a fault finding procedure

make sure the cooling fan is working if so the freon charge could be low

sounds like it ,could be the clima computer ,

I have the similar problem with both my Jaguars, one is a 1988 Jaguar XJS, the other is a 1987 Jaguar XJ6, both blow COLD air out some vents while it blows warm air for heat. I heard it had something to do with the cold air blowing as a dehumidifier, I don't know if this is true, but it is really annoying to have both cold and warm air blowing when I need heat in these cold Canadian winters. If you find out please drop this website a note and let us know how you solved it. thanks.

Has the vehicle overheated recently, if not there is a failure of the Coolant from engine valve controller, that measures flow through the Heater Matrix. Come back with more, as necessary.
Regards,DT

sounds like the blend motor from hot to cold is stuck open half way allowing both temps to come into the car.

This sounds like an air damper is not operating, maybe a cable sticking or a vacuum line come off.

Hi
Sounds like your heater water control flow valve is not operating, and stuck on closed, cold position.

Hope this has been of help.

Good Luck

John.

Hi there is a, dual valve down on the right side of the radiator to split the heat to each side. are the pipes hot where they enter the car be careful       D