Thanks for the update 180. I was using my 2002 Camaro key cycle as a reference (key on, engine off, fuel pump runs until pressure reached then cutoff). I've never listened to the fuel pump in my XF. In case that was the case, I mentioned where the fuel pump is and where the locking module pump is for user isolation during troubleshooting. My exhaust is too noisy for me to hear a slight hiss (I suspect) so I was saying to try with the key on and engine off. Your clarification of course is most necessary. Sometimes, one confuses when posting because we are too close to it. About the hoses, am I reading the three lines are 1(red) to the gas fill door, #2 to the hatch and passenger door, and #3 goes drivers door and console (in roadsters)? If so, I would suspect the leak is in line 2 (as you say possibly a hatch/frame pivot point fracture? It may be just large enough of a leak to allow intermittent activation of the door module based on how much leakage is occurring at the precise instance each failure happens (hatch/hatch-door). No matter what location it is at, the troubleshooting SEEMS to be line 2 of the pump module, would you agree? If it is at the hatch/frame pivot point, there have been some repairs (if I remember correctly) posted in the forum using a male/male barbed aluminum or brass tubing connector sized to the tubing.
PS: Is that 'block diagram' of a RHD system, as it seems to 'reverse' the door connected to the hatch? I didn't see the block diagram until after I replied (used the picture then the text).
.