Right guys I am back with the car having driven in probably the most atrocious driving conditions I have ever had the misfortune to drive in, I wish it had snowed but everywhere is flooded so forgive me that I can't give you a real indepth insight, I only know what I know.
Despite what I was originally informed the fault was actually the parking mechanism not working, thus its default position was locked. The gearbox then went into a failsafe mode preventing any gears from being engaged to stop any further damage.
So the part that was replaced was a N486 parking solenoid. This part was replaced without removing the gearbox as all they had to do was drop off the sump and, with tiny hands the technician stated, there was just about enough room to replace the faulty item.
The gearbox seems fine, I tried all modes and it was faultless throughout the splashy journey home but obviously I couldn't test it fully however it seems they did as there was a few miles added to my total mileage.
I did ask to speak to the technician but unfortunately he was not available at the time however he did ring me later. But, in his own words, he is just a stronic technician and he doesn't know about the different gearbox model numbers, but he could have looked it up I guess.
All in all I feel this wasn't a major defect, solenoids do fail and I don't doubt that they are probably sourced from a third party manufacturer as well. So fingers crossed this is an end to this saga but I apologise for not getting any more information that some of you requested.
