I have an issue with my 2012 XF Portfolio. When I turn the heater on the passenger vents blow moderate warm air,, even when set to HI it still blows somewhat warm air (Not warm enough) although the vehicle had been running for an hour. The driver side vents do not blow warm air what so ever. In fact in a 30F night it was blowing cold air from the driver side vents while temperatures were set to max HI for both passenger and driver. AC works fine when I set temperature to LO it blows ice cold on hot days from both passenger and driver side vents.

Anyone knows what the heck is going on here? Any advice is appreciated before I go and get ripped off by shops.

Thanks

 

May be the DCCV...

(water heater valve)

Read up on it and see if it sounds like it / do some tests.

 

I tried looking that up but everything comes up on older XJ and S type. Do you happen to know a part number or a thread here somewhere?

 

I had a similar issue last spring with the 2010 XF Portfolio, My case ended up being a coolant expansion tank cap being loose and loss of coolant. Once properly topped up, it was fine again. (Coolant on the ground kind of gave that one away though)

I have had other vehicles with similar issues. They ranged from blend doors and step motors failing to thermostat failure and replacement (Thermostats fail in the open position as designed so in cold temps they can not build up enough heat depending on driving situations).... Have you noticed any increase in temp if accelerating for prolonged time? There is also the sensor issues and electronic control modules.