[BB_TX]

Assuming you have a vip211k or z. First thing I would do is pull the top cover off and watch the operation when you initiate a scan. When I set mine on the ground with the handle to the north and start a scan the following happens;
Antenna (dish) rotates counterclockwise about a half turn,
Antenna then rotates clockwise a full turn,
Antenna rotates back to a generally southerly direction,
Antenna begins a series of incremental side to side and up/down movements,
If satellites are found, it will remain in that position and the receiver will start searching for signal.

Sometimes mine will not find the sats at that position and will rotate to an easterly direction and again do the incremental side to side and up/down movements, then rotates back to the south and repeats the incremental movements. It will almost always find the sats the second time to the south.

This will at least show if the motor and drive is working. Then you can call King Controls and see what they say.

I would do the above with the cable connected directly from the Tailgater to the vip211 to eliminate any possible internal wiring problem.