So the up til now reliable old 4.2SC has left me stranded. The car has decided not to start and my code reader has thrown up connection issues with the vehicles security system and immobiliser. I've checked the battery terminals, wiring and fuses and all seem OK. The key fob has had a recent battery too and is flashing as normal. Any idea where I should look next?

Have you tried a battery reset?

Seems to be water ingress into the back of the fuse board in glove box shorting it out 😕

If you do tackle it yourself? Be careful undoing the main harness sliding clips as they love to snap as they get older and this can plague your long term ownership with electrical gremlins sir… 👍