gents i think i have an interface board problem with 1 of my trucks.very intermittant truck will run slow and acts as if tillar and foot pedal safety switchs have been bypassed. you can drive truck standing beside it with tillar in upright position. power off and restart cures it for another couples of days or seven longer.only link i can see in the book is the interface board on the controller. am i on the right tracks ??.