Some how, I think I went through this issue a couple of years ago and the dealer charged me some outrageous amount to change a sensor or controller or something that was within the wheel well of the passenger side, but memory may be failing me and I am not finding the receipt, which I am religious about keeping.

Suddenly I have virtually no control over what comes out of the various vents. I normally set the temp to 71 and the trusty old Jag maintains accordingly. On warm/hot external temp days it almost feels as though there is a direct engine compartment line through the dash vents. Like I could heat a meal on it. When it is a cool or cold day outside, I have to turn the heat up to 75 or higher to begin to receive heat. You'd think this car was going through menopause

Now, when the mode is Foot/Dash, if necessary, what comes out of the foot is cold (if air is needed) and hot from the dash.

If I set the temp to say, 65 or below, then the dash blows cold as well as the foot, but then I end up putting on gloves and hat :-)

I don't know if it is related, but when it is raining I have to run defrost to control the fog that develops on all the interior glass. They have tested for leaks and there seem to be none. I am not losing water, as all those issues were finally resolved a couple of years ago as well.

And as long as I am on a roll here, within a couple of days of the temp issue beginning, I lost my backup sensors. Last time this happened, the dealer ended up replacing the sensors AND the speakers. I'll post this issue as a separate post, but how can I tell if it is the speakers or a sensor?

Have read many similar, but not the same, posts on here but am not sure where to start. I do NOT have a left/right - driver/passenger side issue. The Hot/Cold is equal opportunity :-)

 

Educated guesses:

1. Faulty Dual Climate Control Valve (DCCV).

2. HVAC system is very low on refrigerant.

3. Failing compressor.

One or all of these components could be in play here....

 

Is the Ext temp shown OK?

 

To JagV8 - yes, the external temp seems to be fairly accurate.

Ironically enough, I believe it was the battery. Opened up a new can of worms, but the condition seems to be gone - at least for the moment. AC works as AC should - heat works as heat should. Hot coming from floor and dash. Cold coming from floor and dash. Will see what tomorrow brings.

Sunday afternoon - everything closed - go shopping with wife and plan to go onto a movie and the battery is dead as a door nail. Call to son-in-law for assistance. He stops at Sears to get a new battery, bless his cotton picking heart. While we are in the movie he changes the battery out. So now everything seems to be running correctly, except that the Apply ParkBreak/Parkbreak Fault, Break and ABS warning lights. How do I reset to come back to normal?