I am looking for some advice with regards to the climate control system in my 1987 XJSC Cabriolet. It was working fine, then the next time I needed it nothing happened when the switches were operated. No fan, no heat, no sound.
The temperature control must have been really torqued because when I took it apart to investigate, the whole potentiometer had been through 360 and was totally trashed with wires pulled off. I replaced it with a new switch, but still nothing. I checked all the wires and fuses and eventually decide it had to be the electronic control, the piano box, part CAC3082. On checking the voltages on all the pins, very few matched those listed in the shop manual. I bought a used replacement, but it too displayed all the wrong voltages.
Does anyone know if some Jaguar enthusiast has unraveled the code for the piano box? I have access to computer wizards, but they canÔÇÖt do much without the code.
I understand that new ones are available for $2000 or so, but this is a big fraction of the value of my car!
Any suggestions as to how one can bypass the box and switch things manually?
It would be nice to have the de-mister, and perhaps some heat!

Submitted by bonnettoboot@e… on Sun, 03/27/2011 - 23:42

Well everyone is wondering why you need AC in Alaska! Just joking. The odd issue here is you said it as working fine (on both hot & cold) ? Then at some point the temp control was destroyed by someone! When did it last work & has someone else had the car or worked on it since? That besides, there could be an number of issues, first check the fuses. If OK, it is most likely an amplifier problem, most classic part suppliers stock the modified replacement which is not very expensive & fairly easy to fit, some od the established shops may have the jaguar test unit.