Hi RachelMcC,
Congratulations on the new Cyclone and welcome to the Heartland Owners Forum.
I'm not familiar with the Cy 4018 layout, but let me give you some general thoughts.
In the Universal Docking Center (UDC), you probably have both satellite coax connectors, and a cable coax connector. Usually the cable connector is not on the same surface of the UDC. So make sure you're connected to the cable connector.
Inside the coach, there is a signal booster. Not sure where it's located in your rig, but it's often in the bedroom. There's a small push/push switch and an LED light. The booster must be ON for over the air TV, and it must be OFF for cable.
Assuming you're trying to watch in the living room, there are probably two coax connectors there: one for antenna/cable and the other for satellite. You should be hooked up to the antenna/cable connector and the other end goes to your TV's coax input.
Note that in some RV parks, a set top box may be required, which would be connected in between your coax connection in the living room, and your TV.
On the TV, you have to go into the menu and select between Antenna (Air) and Cable. Then run a channel scan to pick up the available cable channels.
If you don't get anything, it could be that the living room coax connectors are labeled backwards. Try the other one.
If it still doesn't work, and you have a long enough piece of coax cable, try connecting at the signal booster and run that to the living room TV. That would verify the 1st portion of the cable run.
Finally, although it's relatively uncommon now, it used to be fairly common to have poorly crimped coax connectors that are loose, or have strands of the ground shield touching the center connector. If it still doesn't work - check there.
Let us know what you find.