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How do gents.

I have came across a rather odd fault with my rs.

If I inset the key and turn one click to wait for the check status, I get the red box gearbox fault. And when I plug in the vag, sure enough it say solanoid 2 short to plus.
The odd part is that if I start the car straight from key in (skip past first click faster than the car can register for check, the fault disappears and normal service (re box gone) is resumed with now fault code (after initially clearing the code though.

I do, however alway have "right engine mount short to plus" always coming up regardless of how many times I clear it.

Would I be correct in assuming that the fault is loom related and could the engine mount fault be causing the gearbox fault or is it more likely to be a needle in a loom stack job.

Has anyone else ever had these symptoms?

The solanoids were changed by the previous owner a few thoudand k before I bought it.

Any pointers would be greatly appreciated.

Well, I thought I would update this thread for future reference. It would appear that I have managed to diagnose ( by trial and error I may add) the problem from my TCU.
Managed to get a replacement from Peter who is breaking his RS (top bloke to deal with by the way, got the parts sent really quick and he was supremely helpfull).
First off I checked the loom for the appropriate resistance, and all came back fine. Then changed the box loom (p.s I now have the old one as a spare is anyone is interested), but I was still getting the fault code.
Swapped the TCU and it straight away no fault code, and selects all gears.

Haven't got her off the stands yet and taken for a proper run but initall signs look positive.

So moral is- from my experience- short to positive gearbox codes after first turn of key relate to a faulty TCU

The question is, is it worth getting the original repaired?

Depends on how much it costs. Does that place in Heanor rebuild faulty TCUs? They do ECUs and all sorts. They're supposed to be quite good. It could be something really dumb like there is a short in the connector or something comes lose, assuming it has a molex type of thing to attach it to the car.

You're unlikely to get another fault. If you've got a working TCU then happy days. I wouldn't trust anyone to "repair" one. It sounds like a good way to throw money away and get frustrated.

I personally would take it apart to look for anything obvious wrong on the PCB, but you are unlikely to see anything. I have successfully fixed a water damaged ECU in the past by resoldering all the components but it's a Hail-Mary job.

Or you could try reflashing the EPROM in case it's become corrupted, but the most likely scenario is a burnt out IO pin on the controller and that's not practically fixable.

Thought that may have been the case.

Well it's of to the MOT station for me, and back out on to some highland valley roads as it's been 8 months since I last had her out.
Over the winter I seem to contemplate parting and buying something a little nimbler- but as you all know- that turbo'd v8 burble is very hard to part with.