My B7800 HST just let me down. It started like normal then shut down after traveling 5 to 8 feet. Restarted right up then shut down again. It always restarts and will run in neutral with no problem. I have since tried it in neutral and it seems to be a problem with movement of the drive control pedal as it shuts down in neutral as well as when in gear. Short circuit , sensor or what,any thoughts?