Inspired...electronics question

[SeabeeMan]

The last thread on electronics made me remember that there is a lot more going on here the boolit knowledge, so here goes.

I acquired a high end elliptical for a song from my employer last year and was told it worked perfectly. Turns out it doesn't, the guy who told me that quit days afterwards, it's not worth making waves at work over this, yada-yada, I'm stuck with it. It is a Star Trac Natural Runner Plus that, even re manufactured, still seem to fetch well over a grand. I've been in contact with the company and there is no support to be had and I'm not willing to throw money at a professional repair. I cannot get it to enter any sort of program and have gone through all the troubleshooting in the manual, and parts seem to be no longer available.

This thing gets its resistance from an alternator and a gigantic resistor, much like this:

http://scoraigwind.co.uk/using-a-high-power-resistor-as-a-dump-load/

Rather than a mechanism that tightens a belt driving a flywheel or clutch of some sort. As it sits, you cannot change the resistance since you can't get into the programming. Would it be possible to wire up a rheostat somewhere in the alternator/resistor circuit to control the resistance? I assume the more load taken off the alternator by the resistor, the more the resistance, but we all know what happens when we assume.

Any guidance on where to go with this?

[TheDoctor]

The no support generally means they have a different model, and want to sell it to you. Probably new and old use the same major parts. If you can track down the OEM, I am sure you can find any parts you would need. As far as the programming, all I can say is search around, the lit on how to do it will be somewhere. If you were in TX, I could take a look at it for you....

[MaryB]

Disconnect the battery and let it sit for 15 minutes with no power. That will often reset confused CPU's. Looks like the program part is in the upper display board and the only seller of that I saw wanted $675!!!!!! Reseat all the cables, maybe something came loose when it was moved. Especially on the circuit boards and all keypads. If a keypad cable is a little crooked it could be holding a data line low preventing the CPU from accepting commands.

If I could find a schematic for it building a switch box to vary the resistance of the dump load would be easy enough.

[SeabeeMan]

When you hop on and and start striding, which is required to make it start up, it runs through the "StarTrac" start up screen and then never enters the mode where you can select programs, vary the resistance, etc. Keep pressing keys and it eventually gives a "stuck key" error.

I'll dig for a schematic and tear back into it to check cables. It has been left with the battery off for several months now as I didn't have the motivation to mess with it over the summer...or the desire to run indoors.

[MaryB]

So it is reading the keys until the buffer fills up... sounding more and more like a corrupted CPU board. Main program glitched in the pre programmed memory. I didn't read the entire instruction manual so I don't know if the memory can be flashed and rewritten.