Phenomenon: Press the trigger, the propeller does not rotate or rotates occasionally.
Solution: The issue may be caused by the poor contact of the throttle interface or the thumb wired controller (or handle bracket) is faulty.
First check whether it is caused by poor contact of the throttle interface, if not, replace the thumb wired controller (or handle bracket) for the user.
The troubleshooting steps are as follows.
First please check whether there is boot sound when Subnado is turned on? If there is boot sound, it means that the Subnado main unit is good, the problem may be caused by poor contact between the main unit and the thumb wired controller.
 Turn off Subnado and unplug the thumb wired controller, then check whether the 4 circular metal contacts of Subnado for water or corrosion? Please wipe the 4 contacts with tissue or clean soft cloth dipped in alcohol, and take a photo of the contacts after cleaning.
 Please check whether the 4 metal pins of the thumb wired controller was stuck or not? If the pins was stuck, please use a small tool such as toothpick to set the pins back to its normal state, and take a photo of the pins after checked.
 Turn off the Subnado, unplug and plug the thumb wired controller for 3 to 5 times, and make sure the waterproof cover is rotated to the fixed position (as shown below), and then power on the Subnado to test whether it work well.
At last, if you have other the thumb wired controller (or handle bracket) or Subnado main unit, please try to do a cross test to check whether the thumb wired controller or Subnado main unit has problem.