I had the same problem, I followed the user manual for "PROBLEM: The display of the console does not function properly" to remove the hood (mine had 3 screws not mentioned) then there was an electrical wiring diagram and unplugged the incline sensor, started the treadmill, then plugged back in and restarted it. Everything works great now.
Here is the user manual.
http://www.iconservice.com/pdf/IMTL591051.pdf