So I have a 2009 TDV8 and have a similar issue. Does the bypass loop fit on each of the modules or can it be applied in the boot? IE/ does the dash have to come out here to test which component might be triggering the "temperature error"?

Yes, all the rear modules can just have a fibre optic loop plugged in one-by-one.

If, and once you've ruled out all of these, you can access the fibre optic plug to the CD changer by removing the glove box. You don't need to remove the whole dash to get to it. 2015 Range Rover Autobiography 4.4 SDV8

Thank you so much Gary. So far it does appear to be the Hybrid TV Module - because the temperature error has not re-appeared since the loop was put in place over those connectors. Fingers crossed it stays that way!