I'd stay away from those guys and that shop.
I must say I'm a bit baffled you could be here nearly 8 years and not be further along the learning curve on the S-Type HVAC than you are! If you've had that 03 S-T since you joined in 2010, you've been truly blessed to be facing this issue only now.

Use Search to find Karl's epic HVAC troubleshooting thread and it will set you on the right path. Sorry, but his username is KRwxyz where wxyz=some number sequence I can't remember - think it has maybe a 9, 8, and 7 in it but I can't recall what order...so can't help you much with Advanced Search; but the thread should be easy enough to find with keywords: Try DCCV, HVAC, and maybe air conditioning or heater.

Or I imagine Karl will be along shortly to direct you to it. All things are possible, of course, but I've not heard of anyone replacing the HVAC case to mend an S-Type heating/cooling issue....ever!

 

+1 on never having to remove the heater box assembly other than for an X200 with a leaking evaporator core.

Use the search function to find relevant information:

https://www.jaguarforums.com/forum/s...ol-how-185002/

 

Stop by your local shoe store and pick up a pair of good quality running shoes. Don't skimp, get a good name brand. You will need them for running at top speed away from this shop.

Even if they offer to do the job for free, do not let those mouth-breathers touch your car. Temperature control is done by modulating coolant flow through the heater core. There is no door for temperature control.

Looks like Norri beat me to it, but this link should steer you straight:

https://www.jaguarforums.com/forum/s...ol-how-185002/

Post #2 details how to test the DCCV, the most likely cause.

 

Wait....NBCat is just Norri by any other name?

 

 

Thanks KR......you said a cup of coffee huh? More like a pot! LOL!!! Still reading it and will get to the meat and potatoes soon. Keep you posted, wish me luck.... and thanks for this, my hopes are much higher now.