Rear demister partially working - help!

[VR46]

I've searched the other threads but can't find anything relevant to my issue, so here goes:
We have a 2017 102 Transporter with tailgate. The heated rear window only clears the top third of the window and always has since we got it. I've tried to ignore the issue but can't any longer with winter looming.
My thinking is that there is only a single electrical connection to the rear window and therefore the issue must lie within the window wiring itself. I can't see any visible breaks or issues but I just want to confirm that my thinking is correct before getting the window replaced. Any help is greatly appreciated!

 

[DaveCrampton]

Can't you buy the foil sheets anymore? I remember seeing the foil sheet being applied in the Hynes Manuals.

Google's... It would appear not.

 

[seewhy]

I fixed this on a previous van with a special pen. I know it sounds stupid, but it is basically a conductive ink and you just draw over the line from just before the non-functioning section and it fixes the connection. The crack could be minuscule so may not be visible. I hope it's obvious that I mean draw on the inside of the window.

I think if you search 'circuit scribe' or 'conductive ink pen' you should find something. My sister-in-law came up with this one - she used to work in the automotive industry, so knew what she was talking about. Helluva lot cheaper than a new window, takes a couple of minutes, works.

Of course if, these days they laminate the heater element within the glass this won't work!

 

[prog99]

I fixed mine with the pen as well.
I had added advantage of a thermal imaging camera which makes it dead easy to spot the breaks.

 

[DaveCrampton]

This is v useful as my Passat has had only half the window cleared since I bought it 5 years ago! Thanks

 

[rod_vw]

Maybe worth a look here Amazon.co.uk : heated rear window repair kit