2004 XJ8 Radio Amplifier (or not?)

My car has factory radio with CD changer in the boot, no subwoofer.

Problem is no sound after main battery replacement. Radio head appears to work normally, LCD is alive, stations appear on display, tone controls change normally.

Does the radio head drive speakers directly when no subwoofer option or does it also require a separate power amplifer?

In the boot fuse box is fuse F34, 30A, not blown, protecting a power amplifier that I have not located.


I assume your car is an X350, being MY2004.

Have you looked behind the left hand side boot side carpet? You should find the answer there in the form of an amplifier.

Kind regards,
Bard Thomas

My 05 VP is in the shop now for the exact same problem. Everything displays correctly BUT NO sound. I replaced the amp with no joy. The shop thinks it’s a break in the fiber optic network. They are saying if one part of that system fails, the complete system is messed up. Each component is connected to the system. I HOPEFULLY should know more soon. I will update.


Hi Richard,
I have this exact problem unresolved for years ('04 VP) and now use bluetooth speaker with IPhone.
I also replaced the amplifier with no result.
Have you come up with the necessary repair yet?

Hi Steve,

Short answer, no! The car is at my friend’s shop, and he looking at it. He said it’s definitely in the the “fiber optic” network. Each component is connected with this network. If there is a break in that network, there is no sound. I did get a replacement network cable for all the trunk components (amp, CD player, & navigation) yesterday. I’m taking this to him tomorrow and will update when I know more!

PS I’m also wondering if the head unit is not sending the signal to the amp!