I have 3 of the units. My understanding is that the remote sends a signal to the display unit to change a parameter. Simply, if the remote works when the display key pad doesn't, it ain't loose wires between the display and the control box, it's more likely in the display key pad. I use the remote almost exclusively as it's more responsive. Might try changing the batteries in your remote.
I'm tired of fast moves, I've got a slow groove, on my mind.....
I want to spend some time, Not come and go in a heated rush.....
"Slow Hand" by The Pointer Sisters