2001 VDP - What is the black cable nicely tucked on the left trunk hinge? Looks like a coax cable and mine is broken. Can't be the radio antenna cable because the radio works and the antenna is on the right side.

 

My XK has a wiring sheath running up the right hinge. Don't know about the XJ. Wiring goes to the tag lights and in my case the deck mounted 3rd brake light. And it is a common point of wiring breaks.

 

Antenna for cars with Nav system? They typically throw the same wires in every car but only utilize the ones that have the optional equipment necessary for them.

I read that the X300 XJ6 premium sound system has like 13 speakers but only 9 are used. The standard system's speakers are still in the car but not connected.

 

I got the premium system (Alpine) without navigation in mine. The front door speakers (brand new) are still making the same buzzing noise like the old ones only at low volume. Someone suggested bad amp. I don't know where else to look and I don't want to waste money on a used amp if I don't need it. I bet you my factory speakers were ok. Now I'm looking for loose/broken connections.

 

I would suspect the amp, but it depends on the tone of the noise. I'm a huge audiophile but no electrical engineer. If it is a noise that changes with engine speed, look for a ground wire problem. A inconsistent staticy sound would be loose speaker wires. Although the following would probably cause a noise in every speaker, but do you have any aftermarket accessories attached to the sound system (this can even be a mp3 player connected via tape adapter)? Try disconnecting the CD changer. Maybe that is the source of a ground loop?

These amps are actually 6 IC amplifier chips in one box (4 for the door speakers and 2 for the sub). I think they are made by Toshiba aka low quality. Try changing the "seat position" setting. If it changes anything, its the active crossover which is inside the amp. Only the front 2 speakers have the active crossover.

Has the sound ever gone away?

 

The only thing near the left hinge is a black rubber hose, part of the fuel/vent system.

The ICE harness go on top of the left wheel arch.
For the USA Jaguar did use specific harness, depending on the options.
That why I had to change the whole ICE harness ( from the left of the trunk, through the C post, underneath the rear seat, carpet, center console up to the radio) when I added navigation to my car

 

Subwoofer on the rear deck has wires stemming from a main harness near the left trunk hinge, the harness channels them to the amp (which is above the CD changer behind the insulation-cover.)

Only premium sound XJ's like our VDPs would have this.

 

Like I said, mine has one on the left hinge and looks like a coax cable.

 

Maybe a mobile phone antenna?

 

Post a picture and we can guess better.

 

I think it may be the Alpine AI-Net cable that connects the amp to the headunit in the Premium system or to the CD changer to the headunit in the standard one.

 

The buzzing sound never went away, I have no aftermarket accessories installed, the sound doesn't change with engine RPM or other. It sounds like a busted speaker but only at low volume listenings and only in the front doors.

 

The mysterious black cable in the trunk was a coax cable installed by the previous owner and I took it off now because it wasn't connected to anything.
Got a new (used) amplifier from eBay and installed it today; the buzz from the front speakers is gone. Thanks