I have an 03 XK8 with the Premium audio system. I noticed today that the sound of the system had changed and investigation revealed that four of the front speakers (two in the fascia and the Alpine tweeters in the A-pillar) had stopped working.

The electrical guide indicates that these are driven in parallel from the rear-mounted amplifier. It didn't seem very likely that both channels of this would have failed simultaneously, so my first thought was the multiway connectors in the door pillars. These were separated and cleaned with propanol and a toothbrush but it didn't help.

Before I dig into the amplifier and its wiring, are there any interim connectors that might be worth checking and which are common to both channels? Alternatively, has anyone had this problem and can suggest a quick fix?

 

Did you already check the fader setting?

 

Yes. That's how I established that all four front speakers had failed.

I've carefully checked all fader, balance and position settings. Looking at Fig 16.2 in the 03 XK8 electrical guide it's as though IC15-7, IC15-17, IC15-8 and IC15-18 have become disconnected. Given that the fascia and A-pillar speakers are driven in parallel, I assume that the HF crossover is done in the amplifier and that both sets of speakers function as simple tweeters.