When fault occurs by-pass and high speed do not kick in. Runs on half power with throttle pedal released. It happens when truck is under load.Works o.k when wheels off the ground. Resets when put into neutral and reoccurs when put into fwd/rev and throttle reapplied. Throttle assembly is not sticking ( no cigarettes butts) It does have micro switch and test good. Throttle output to the card is within range and does not hold when fault occurs.