Hello Howitt, I am sure it is suppose to go full forward when the belly button e-switch on the top of the Handel is activated. its a safety feature to stop someone from getting pinned buy the truck. you have to release the handle in the upright position or turn the key switch off/on to reset the drive system. You may have some dirty or stuck fwd/rev contact assemblies. ( Usually caused buy low battery volts)You may also have some wires mixed up recheck and triple check wiring.