Troubleshoot motors won’t start

[Espong5532]

Hello, first time on the site and I am looking for some help troubleshooting a problem with my phantom three standard. I have been flying for a while but not very regularly. Haven’t had any major problems till now. All of a sudden I can’t start my motors. When I cut the battery on it it goes to solid red lights and slow flashing yellow lights and the lychee app indicates that it’s disconnected and I cannot seem to get it connected. I recently detach the propeller guard brackets and use the long screws to go back in. I am concerned if I did something to the motors. They seem to spin manually OK. Anyone have any suggestions on what I can do to diagnose this?. Thanks Trey

 

[N017RW]

Yes, the longer screws cannot be used without the guards.

If you fully inserted 1or more per motor then the motors are damaged beyond repair.

This is an unfortunate situation but one that is reported here often.

Carefully inspecting the fine motor coil wire at the ‘bottom’ of the screw hole will show the damage to the coil(s).

 

[Espong5532]

Would bad motors keep the receiver from connecting? The receiver stays red lit and doesn’t turn green
Thanks for you reply

 

[Espong5532]

Ps. I went ahead and bought some replacement motors but before I take the old ones out. I compared the new spin feel to the old spin feel and they do t seem very different and I’m wondering if I jumped the gun on my diagnosis of bad motors jumped the gun on my bad motor diagnosis

 

[N017RW]

You won’t be able to detect coil damage by spinning the shaft/prop.
The coils are stationary.
You have to look down the hole to see damage.
However, if you fully inserted a long screw it has certainly damaged the coil underneath.

 

[PhantomFandom]

Ps. I went ahead and bought some replacement motors but before I take the old ones out. I compared the new spin feel to the old spin feel and they do t seem very different and I’m wondering if I jumped the gun on my diagnosis of bad motors jumped the gun on my bad motor diagnosis

As mentioned by @N017RW , you can only see the damage by looking at the coil from the bottom.

Please note that replacing the motors is not a trivial process, especially if you are not familiar and adept at working with small electronics. You need to disassemble the drone and you will need to solder the new wires in place. Do NOT attempt to splice the wires in with the old ones as some have attempted in the past. Also make sure to fully strip the end of the new wires as they usually come with a protective (and pretty much invisible) coating.

GOOD LUCK

 

[Espong5532]

Thanks. I got the motors replaced and soldered Fired it up and everything looked rosy, motors all spinning in the correct direction but when I accelerated it will not lift off. The motors all accelerated like they should and it seems like everything is working but still no lift off. Could these motors take a different propeller .? Or something else?
Any advice is greatly appreciated.
Thanks

 

[N017RW]

If your motors are all spinning up to take-off speed(?) and no lift-off.... must be backwards rotation, all the way around!
The proper rotation at each arm/corner is indicated in the molding of the shell itself.

Of course it must be the correct motor (shaft thread direction) and prop on each arm to create downward thrust. This can be an issue since a BLDC motor will happily spin in either direction depending on phase rotation.

Standing behind the drone - and viewed from above...
the Left front (M1) and Right rear (M3) motors spin clockwise,
the Right front (M2) and Left rear (M4) motors spin counter-clockwise.

 

[Espong5532]

That’s exactly what it was. I had to shift all the motors over one position and up it flew. Thanks for taking the time to reply.