16 minutes ago, Breezy_Pete said:

Fair enough.

If you have any further trouble, it's probably not too hard to get to the source of these wires beyond the holes in body and tailgate, and replace the sections which go through the bellows, with splices in areas that don't flex when the tailgate is moved.

That’s a great tip. Crimped up for now - if I get future failures the loom will get too bulky with crimps for the rubber shroud. So will have to go down the replace sections route. (Fingers are crossed for now)

On 15/08/2025 at 17:18, Breezy_Pete said:

I'm not convinced that super-thick black wire is an original part of this car. Might be a 'this is all I had' repair bodge previously.

Can you not take the tailgate trim off and see where it goes to?

@Breezy_Pete Mine has a thick black wire too and I'm certain no-one has ever been in there before. I have the 2017 edition of the manual and there are seven diags of heated rear window wiring, but I have just noticed that all of them have an asterisk against them which equates to "models with no rear window aerial" so I'm wondering if ours and @spig212 have one so the wiring is a bit different. Our car has a panoramic roof so it certainly doesn't have a roof aerial.

Possibly a coaxial cable then?

The black wire is not coaxial as there was no screen braid. My thought is that drawings were updated but wiring looms hadn’t caught up for our cars. (Thinking the mk2 loom was common and used for early mk3)

@Breezy_Pete My black cable isn't co-ax either - you can see the strands in my photo earlier in the post, where the insulation has pulled apart. The manual mentions panoramic roof aerial as well as heated rear window aerial so it could be either, and the only way I'll know for sure is a quick check in the tailgate at some stage to see if there is box in there.

@spig212 Ours is March 2016, so fairly early (we don't have a brolly/holder 😪 )

Guess we won't know for sure but since my loom is bad enough to do something with, I'll probably know more when I have gone through each and every wire and cut new in. That's a job for another day though!

Edited 19 August, 202519 Aug by Yorkshiremidge

Hi, I have the same issue with my Fabia, but only the number plate lighting not working, I'm planning to have a look later this week when I get chance to have a look at the car in daylight, does anyone know where the end of the loom which passes from boot ends up, is there a connector behind the seats somewhere as it may be easier to remove this to initiate a proper soldered repair if there is some slack in the cables? Many thanks for the great advice already in this thread!

Nick.

@nickrfrank The wiring diags indicate there is a ten way connector "on left in the luggage compartment". Makes sense as the (expensive) rear loom section a dealer would fit to sort this fault out isn't that long. Not gone looking yet - but I assume it might be hidden behind the side trim panel.

I can confirm there is no slack in the cables as that is why they fail ☹️ Just jointing broken wires back together won't sort this properly. What I was planning to do was let in new sections of cable for each circuit such that the joints at each end are tucked inside the tailgate and C pillar, and only the new cable is going through the grommet.