Jeffrey,
Sounds like you either have a blown fuse or bad relay. Remove the floorboard and look at the relays at the left side against the frame closest to the battery. The top row of relays left side should be the hydraulic relay. Install new relay or swap with one similar. If the hydraulics still do not work, raise the hood and look toward the back. You should see a small black cover, under will be the fuses. With key switch on, check both sides of the fuses to make sure you have voltage. Do you have the login password for servicing the lift? If not need to call for a tech. If so, press the right arrow key twice, you should see an entry for the password. Once entered the screen will return to the main menu. Press the right arrow key four times until you see a little man. This is the setup menu. Press the enter key to access menu. Scroll down until you see a battery. Press the enter key again and see what the truck voltage is set at. Check the model number, in the middle should have two numbers. This is the voltage of the truck. Make sure they match.