I have a 2003 Jaguar S Type Supercharged. When the Nav/Entertainment System is turned on, the screen in the console comes on and the Navigation function works well. When the radio or CD function is selected, the screen indicates that the radio, etc is on by saying so in scriopt on the screen. It also shows the radio etc is turned off when that is selected. But no sound comes from it and the CD stacker in the trunk does not become active although a CD can be loaded or ejected. I have searched using Google for info on troubleshooting this unit but have not found any thread that deals with this problem. I have checked all the listed fuses and they are all intact and passing current. I have no access to a working system that I might be able to "borrow" known working parts from. Can anyone on this forum suggest anything I should check besides the fuses?

 

is the screen functioning correctly did you mean ? or is this something new?
if the screen is acting up it could be a software glitch , needing reprogramming
or a dead module causing the glitch .
if the screen is functioning how it should . and there is just no audio/sound -

try checking all the d2p fiber optic connectors are seated with a strait connection and are clipped in .
start behind the audio stack then failing that behind the screen / radio module
search how to, or
down load a copy of jaguar JTIS , for diagrams
1 common failure is the rear mounted premium amplifier , prone to get wet when cleaning the boot/trunk shut.
or corrosion .

 

As above.
Has this ever worked?
Do you get the audio sat nav instructions or it it silent?
Do you have premium sound. (Alpine badges on the door speakers.)
With the standard non premium system the amp in the head unit powers the speakers via a two wire connector.
With the premium sound option the amp in the head unit is disabled and the amp in the boot powers the speakers via a multi wire plugs. (If you fit the amp you also need the premium speakers as well.)
If you have the premium system the d2b fiber cable network takes the audio as a data signal from the head unit to the amp in the boot, this will only work if you have a complete loop on the d2b network, any plug not connected will stop it from working. For example if somone removes the phone or voice modules from the stack in the boot but leaves the d2b plugs the system will not work.