I fixed it!! I still need to reassemble all the pieces and move it out of the garage and into the house. But I got it to work!
My in-laws bought a pretty expensive treadmill a couple years ago. It stopped working one day. Since it was under warranty, they had a service man come look at it. He replaced the motor controlboard with no luck. Call number 2 the guy replaced all the other boards. Still no luck. After that they gave a full refund and left them with the treadmill.
The Boring Details
So for the past week, every day after work I would spend an hour or two disassembling every component and inspecting it for any defects.
Today I attacked the monitor, since I’d yet to see it turn on. While unplugging and replugging each connection, one of them I noticed glue. Looking closer I realized the plug came out with the jack. The pins were bent on the board. I took it out and opened it up to reattach the jack. The jack in question was the power.
Once fixed I plugged it all back in and was able to use the bezel buttons to control the display. On a whim I checked if the other controls worked and sure enough they all worked. A short in the display cause the whole control panel to lock. The display was also the one thing they didn’t swap out.
So now I have a nice treadmill that I probably wont use for the next 5-6 months.