OK, I have changed radios from a 3PM to the 2PH and lo and behold reverse has returned. So it is a radio setting on the 3PM. Now I just have to work out which setting it is. I did change the neutral range on the trigger to 6 degrees so I will change that back to 12 degrees and see if that works then have a go at trim and any other suggestions people have made to try. But I think I agree with one of the comments above that it is a programming issue, as the trim or neutral range shouldn't affect the operation of the reverse function.

Any other suggestions would be welcomed.

Nick