My Proform Treadmill 830 qt quits running after 45 sec. I have tried it on all settings/programs and it continues to happen. When I step off the walking board/belt it picks up speed again, but immediately stops when I step back on. I am not over the weight limit. I just bought this from somebody and don't have any of the history of use, etc.

Nikki Neville, August 2010