Hello again.I have manage to get a blow up of the gearbox and there are 3 speed sensors,all identical according to friend all Number 11?? does anyone no what the 3 are for ??or which 1 tells the ecu when to change up ?? poss 1 for when to change up,1 when to change down,other 1 reverse ?? just a guess Ta Dave The VSS is (going from memory here) next to the right hand output shaft. Just above it. Of the other 2, one is the TSS that measures the Torque converter speed (going from memory again) and i cant remember what the other one does. Sufice to say, they all do different things. They are all used to work out when to change up/down. Any one failing could put the gearbox into limp home mode. Based on the diag error, I'd go for the VSS 1st. Steven