(ET) Strange Alltrax behavior

[Steve Gaarder <gaarder1 ecovillage ithaca ny us>]

I have an E-15 with an Alltrax controller.  The speed control pot is 
on a throttle lever and the foot switch is controlled by a separate 
switch.  The first time I start it up it's ok.  I turn on the key switch, 
the contactor closes and then opens a few seconds later.  I turn on the 
"foot" switch, the contactor closes, and off we go.  It's all fine till I 
turn off the foot switch.  After that, it will not run.  Turning on the 
key switch makes the contactor close, again for a few seconds, but it 
never closes again, until I let it sit turned off for 15 minutes or more.

Any ideas?

Steve Gaarder