Well i see you posted this in two places,and think you have a tiger tank.When you said below the tank moved without any control input ( did you have it next to some type of power source that can cause interference with the transmitter,do you always make sure your transmitter is turned on before you turn on the tank.And always turn off the tank before you turn off the transmitter)If the board is faulty,I can not help you there except to tell you to replace the board.I would take the three screws out of the turret motor first,remove the motor from the mounting posts.Turn the turret back and forth and make sure it is moving freely and not binding or hanging up on something.If the turret seems to move OK,the next thing I would test is the motor itself.To test it ,you should unplug the 8 pin connector first.If you have a spare male plug that plugs into a battery it is easy to test the motor by touching the plus wire to one side of the motor terminal and the negative wire to the other motor terminal.If the motor runs OK you will have ruled out a motor problem.If all the above is checking out OK,then I would start checking the wires and any connections from the motor to the board.If this motor binds up when trying to move the turret,you are going to see smoke comming from the board.When ever you see smoke comming off the board it's not good news.Some times if you see it quick enough you can get lucky and it may still work(depending on what part of the board got hot)---------Hope this may have been some help to you,and Good luck--------BIGMIG [:-][:-][:-]