Hello folks,

I recently fitted a reconditioned auto-box from Ashcroft Transmissions. All was going well until last night when I got a 'Transmission Fault' message and the box went into third gear 'limp' mode.

Thanks to my newly acquired Nanocom (thanks DaveAll) I was able to read the code - output shaft speed error.
I reset the code, set the Nanocom to display the live readings and with wife reading out the speeds I went for a little dive. All was good.
After she went back indoors and I had a bit more of a play I got another 'Transmission Fault' warning, this time the fault was the anti-stall solenoid (or words to that effect).
Again it was cleared and all is good.

I am suspecting I have a bad connection in the loom somewhere. The greabox plug is securely attached, though I will disconnect and check it is clean. What is the routing of the rest of the loom? Are there any multiplugs elswhere known to give problems (assuming this is just a poor coincidence)?

There's a 6 way Supaseal connector at the front of the gearbox loom. On a V8 it lurks behind the LH cylinder head, between the head and the bulkhead, so I would expect it to be in the same place on a diesel. It was that one on mine that caused problems as it looked fine until I touched it and two of the wires fell out. The other one is under the centre console (for the wiring that comes out through the floor towards the back of the gearbox and transfer case) and a real pain to get to but on mine it was perfect. Being where it is, it is pretty unlikely that it can get wet and moving the wiring around is unlikely to disturb it. I would suspect the one at the front as the loom will have been hanging on that when you changed the gearbox. I cut the connector out and soldered it through with a piece of multicore cable (leaving enough slack so it can be moved out of the way rather than having to disconnect it if I need to).

If I remember correctly, Transmission Fault can also be caused by low system voltage, i.e. a bad battery or alternator.

It can yes, but it has an almost brand new alternator fitted and a good battery.

It has so far only done it when I put my foot down after a reasonable amount of driving time (1 hour plus).

When the weather improves I'll have another look.