That's a mighty tall rocker cover you have there😉

It has also been removed, but wasn't a problem as the lid was closing and activating the switch correctly👍

i haven't watch the video yet.    but on an XF etc, always check the glove box light (i removed it to fix the issue, the switch is not up to a 10kg junk box on 2 hooks for hinges )   auto elec found it in 30 seconds, due to it's a common issue. (didn't charge Me, Legend) 

My understanding of "Electrickery" has always been my Achilles heel and never got a good grip on it, especially when you don't use these skills regularly to really make it stick in the old brainy parts...   I removed the old aftermarket alarm that came in my XF van recently because of some random things going on with it, but I also thought this would fix the battery draining issue I was having, but not the case...so I hit up youtube and found a video that I could understand what to try, and low and behold I found something that I never considered being an issue...   I haven't had an interior light in the car for a while (by choice) and as it turns out the passenger side door light switch was not turning off because the door was not hitting the switch enough to turn it off, and I thought no globe meant no current draw, but my testing proved me wrong. When manually pressing the switch no current draw, then let switch go and current was being drawn again...   Here is the video that helped;    

What ever works is fine with me 👍

It may have had other problems I wasn't as good with carbs back then, as much as I thought I was at the time, but you can learn a little bit in 15 years, I do remember it making a huge difference to that car at the time, it made as much of an improvement as putting an efi cam in it and swapping the auto for a t5

I read somewhere only 3.3's had the PTC, but hey it seems there are exceptions sometimes, and anything may have been done in warranty scenarios...  

Not sure if that should make a difference as I think they are virtually identical...mine goes quite well really...

I think the PTC heater, is an XF only thing?

When I was 19 I had an xf wagon I got from the original owner, it had 60,000ks on it it was a 4.1 and was the slowest car I had ever driven (I even pulled the plugs and measured the stroke to make sure it was a 250 and not a 200) turns out it had a webber from a 3.3 on it previous owner swore black and blue the carb was original to the car, I put a webber off a 250 on it and it made a huge difference