Problem with drivers door speaker
 

I have a 1998 XK8 with the HK premium audio system. I have a wiring fault somewhere which results in me having to leave the drivers door speaker (main speaker not tweeter) disconnected. If I connect the speaker the windows stop working. I suspect a short, possibly to the SCP network, as it can effect the passenger door as well. I inherited this issue with the car but decided that now was the time to investigate further. I have disconnected the battery and the door harness connector at the A pillar and looked for a short in the door harness but didn't find anything (see more detail below). I note from the circuit that the speaker and SCP connections are also present in the AC14 connector. Anyone know the physical location of the AC14 connector and how to get to it?
TIA

Here's the tests I performed using a digital multimeter in continuity mode
DD1-11 to other DD1 pins - no short found
DD1-12 to other DD1 pins - no short found
DD1-11 to all pins on DD16 and Door Control module connector pins (having disconnected from DCM) - no short found
DD1-12 to all pins on DD16 and Door Control module connector pins (having disconnected from DCM) - no short found

See this post (EM2 is co-located with AC14)...
https://www.google.com/url?sa=t&sour...d-7ik4nt8_a_0u
I haven't been in yet to further investigate this issue.