motor not running up

[tonycuk]

I have a phantom 1 that I have stored since last flight. It has not been dropped or crashed just simply sat on a shelf awaiting clement flying weather. Idecided to calibrate the imu and compass which went well. but on powering up the motors one is only performining a stuttering motion. Tried sticks at full defelection (no blades fitted) the other 3 all performed well but not this one. Any help appreciated

 

[CityZen]

Open it up and check the connections between the motor and the ESC. Also inspect the 6 MOSFETs on the ESC and see if any look damaged (though it's hard to tell with the coating that DJI applies).
Measure the resistance between the motor wires pairwise for all 3 possible pairs (again note that DJI coats the ESC and solder joints with a clear plastic coating that you'll need to pierce through).
Make sure all 3 measurements are about the same. If so, the motor is probably good, so the problem must lie with the ESC. If not, the motor is suspect. If so, it may be a good idea to replace the ESC as well.

I have no idea why it would just go bad from sitting. Oh, actually I have an idea: make sure nothing metallic got stuck inside the motor. In fact, do this first.

 

[tonycuk]

Thanks for your help. Will update when time permits an investigation