SYMA X8HG one rotation system fail

[RUBENS MAZZON JR]

Hi. I have a Syma X8HG and I have a problem with one of the rotation systems. Three work normally but the fourth only starts rotating after helping with a flick of the propeller. I already changed the plastic parts and also motor and nothing works. Can it be anything related to energy transfer?

 

[mozquito1]

Sounds like an esc has gone. If you changed a motor did you wire it the right way. Check all solder joints. 2 things with the toy grades. The motors are rubbish & if one thing goes on the board, the rest may aswell have. If the motors don't go, the pinyon gears wear down.
Toy quads =2hrs fly time, if that. If you are lucky. Easy diagnosis with toys, motors or fcb because that's all there is.