Hi Andrew - I have the snapon solus pro, and Launch X431, and an older autodiagnose. Both go in to the transfer box however I cant see where to carry out the calibration procedure. There are no fault codes. Looking at the range change activation switch circuit, this puts to earth an output from the main gearbox ecu, which then presumably requests the transfer box to activate the range change. At the moment the only way I can get this to activate, is to insert a fuse into location 37 on the fuse box, which moves the transfer box in to neutral, and the range change light on the dashboard flashes. This is at it should as per the workshop manual, however under no circumstances can i get the range to change using the switch on the center console.

Thanks for your help, this one is a nightmare!!

Roger