[Model flyer]

You don't necessarily have to replace the motors. The motors are cheap brushed jobs like those found in cheap toys and finding the correct one might be difficult.There are two motors per door,one to lock it and another to deadlock . The reason for failure is usually the grease or lubricant gets into the motor and onto the commutator. Easy job but may take a while to find your way around. The motors can be stripped and cleaned with white spirit. The commutator may I need cleaning with very fine wet a and dry like well used 2000 grit but go easy.Tip.plenty of pics when dismantling the lock assembly to refer to when reassembling.