Hi,
To answer my own question~
On top of the gearbox there is a 6 pin multiplug, the two wires needed are black with a red tracer and black with a blue tracer, by shorting the plug out on these 2 pins (2 neerest front of car) by lights came on.
Next step I removed the switch (2 9mm bolts) and belled it out with the multimeter (tested ok when pressed in) then put my fingers on the hole where the switch contacts are and selected reverse to check that the cam on the shaft is ok (is was)
Put it all back togather and it works 1st time, must of been dirt on the switch?
Martin.