I think I read a query about this job by someone else in one of this year's magazines - it may come with a few unexpected complications.

I've had no "park" problem with my XF but had a similar problem with the electric parking brake due to a duff battery. During lockdown so I kept the battery charged in between runs until I was able to have it renewed, no problem thereafter.

This is obviously an old problem, presumably resolved, but with any similar electrical problem apparently caused by damp I would saturate the area with WD40. It worked on all my ancient cars from the 60's onwards so "ought" to work on a modern Jag.