You could have a faulty accelerator, when you turn the key on you should get power to the main controller terminal 1 and the aux contactor coil to power the DC/DC convertor. Once the controller see power it will give a supply to the main contactor. Once the main contactor is energised you need a feed from the seat switch. The hydraulics won't work until you de-press the accelerator. All of the can be checked using the curtis handset.