I recently bought an 03 s type r with navigation which had ice cold Ac but no heat, I found the dccv valve was so corroded it was froze completely. I replaced it and now got a little cold air on drivers side vents and warm air on passenger vents when Ac is on. But the heat is now working.

 

Just make some electrical measurements see what you have on those two control lines. Maybe the repair on your module gave out

 

Be aware that depending on how long the car was operated with a bad DCCV it will eventually take out the AC control panel as well.

Now the good thing is this can be repaired. Note that cars with Navigation use a RCCM (Remote Climate Control Module) and non-navigation cars us a CCM (Climate Control Module). People have repaired this themselves but take some time to read a bit about the entire system? I really like that they can install protection too. You can read why but it was a design flaw from Jaguar. The modules have no over current protection at all and when the DCCV goes bad it almost always starts drawing excessive current which comes thru the module.

This excess current starts burning stuff out on the board inside the module. They have some great pictures showing what to look for on the board too.

Climate Control Repair and Upgrade
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