I got an FM-750 wanting to pair it with an EZ-Steer I made sure to buy the right EZ-steer kit and follow the cabling guide trimble provides. The FM-750 says it that no EZ-steer is hooked up to it when I go to calibrate the unit. I tried all three of the power cables on the harness that comes with the kit. Anybody know what I am doing wrong....cabling, software