Hi Bob Very interesting info there Thanks. I have found the wiring diagram for the system at fault so have a look and let me know your thoughts please

Hi Robert I am working on a MAN truck with off road capabilities and everytime the low ratio is engaged the code for the actuation solenoid pops up stating its shorted to Battery +, I can clear the code and it doesn't return until the switch is operated to select low ratio.

@Robert Shervill Unfortunately no I don't have a wiring diagram for you, all I can say is the system is contolled by a ecu called a VSM which the three way switch passes through to operate a pneumatic solenoid which operates the actuator on the transfer box, the fault code says there is a short to Battery + but I have no idea where it would be in the system and I was hoping to get a plan of attack to find out where to start looking.