On Wed, 5 Dec 2007 14:25:33 -0800 (PST), nearysr
put finger to keyboard and composed:

I have a used Spirit SL 188 Programmable treadmill which from
time to time runs fine, responds to input from the control panel, and
then stops. The duration of its operation seems inversely
proportional to the speed at which it is asked to operate. When it
stops, it remains stopped for days and weeks, with no response to
hitting the reset button, pulling the plug and replugging the unit.
Abracadabra, plug it in and it starts!

Is the display blank when this happens? If blank, then it would appear
to be a power issue, otherwise I'd be looking at the motor (brushes?)
or the motor control board.

The manufacturer tells me over
the phone, based on my description of the above symptoms, that it
needs a new control board which they will send me for $300. I cannot
find anyone local (Albuquerque) who wants to deal with it, because it
is 11 or 12 years old. There is no apparent wear or tear and it seems
nuts to me that this thing can't be fixed. Any advice?

My treadmill (different brand) has a safety key which kills the power
if you fall off the belt. It consists of a plastic key which you
insert into the control panel. This key is linked to your body via a
clip on the end of a string. It may be that the keyswitch contacts on
the control board are dirty.

Here are some troubleshooting tips:
http://www.treadmilldoctor.com/Troubleshooting

- Franc Zabkar
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