I'm new to drones and purchased my DJI Mini 3 Pro approximately 11 days ago.  Yesterday I noticed that the front left propeller motor is stiff and I am unable to fly the drone due to a stuck motor message (did not crash or taken it out to the beach etc, just normal flying in my neighborhood).  I've watched a few videos on youtube on how to fix it with aircans, alcohol, etc.  Can someone chime in on how to properly troubleshoot this issue since it appears to be occuring to others by just reading the comments from the video.  I don't have an issue returning to DJI for repair since I did pay for the DJI Care but if I can avoid having to ship it back and waiting weeks that would be awesome.  

DO NOT wash the motor with solvent, I fear you would damage the lubrication of the motor. A vacuum cleaner or air can would be my approach.
If you have not caused the problem and if you return it, why opt to waste a CareRefresh on it? Ask DJI assess it with a warranty claim in mind. They will almost certainly let you know if it is otherwise, then you can decide what to do.

Have had the same problem with a stuck motor on a brand new drone, first attempt at take off.
Used thin special oil for small ball bearings mixed with isopropanol. A drop on the ball bearing protection plate top, and it found its way into the ball bearing. An hour later, the ball bearing had come loose.

Dji demanded to have the drone inspected, so I sent it in to Dji service and it was confirmed that everything was fine and a decent way to fix this problem.
Had no problems afterwards.

Sean-bumble-bee Posted at 5-28 13:02
DO NOT wash the motor with solvent, I fear you would damage the lubrication of the motor. A vacuum cleaner or air can would be my approach.
If you have not caused the problem and if you return it, why opt to waste a CareRefresh on it? Ask DJI assess it with a warranty claim in mind. They will almost certainly let you know if it is otherwise, then you can decide what to do.

This was purchased through BHPHOTOVIDEO since it was a little cheaper so the 15 day rule only applies if I purchased directly through them.  

Aurgelme Posted at 5-28 14:06
Have had the same problem with a stuck motor on a brand new drone, first attempt at take off.
Used thin special oil for small ball bearings mixed with isopropanol. A drop on the ball bearing protection plate top, and it found its way into the ball bearing. An hour later, the ball bearing had come loose.

Awesome I will try that if I'm not able to find any other solution.  Do you mind telling me the type of oil you used?  Thanks

djiuser_lzpB4pvZYzG4 Posted at 5-28 15:20
This was purchased through BHPHOTOVIDEO since it was a little cheaper so the 15 day rule only applies if I purchased directly through them.

What 15 day rule?
The DJI warranty on the drone is one year irrespective of the retailer, isn't it?
If it's a problem you do not cause it's a warranty matter and shouldn't cost you anything.

Hi there, we apologize for any inconvenience caused by this issue. The propulsion motor of the Mini Series is designed with a spherical bearing. During transportation and storage, the bearing may move within the motor, which leads to the issue you reported. As the spherical bearing cone can be manually adjusted, you can manually rotate the motor to fix this issue. Please power off your drone, and manually rotate the stuck motor. Thank you for your understanding and support.

Sean-bumble-bee Posted at 5-28 17:06
What 15 day rule?
The DJI warranty on the dronr is one year irrespective of the retailer, isn't it?
If it's a problem you do not cause it's a warranty matter and shouldn't cost you anything.

I spoke to a DJI rep over the phone and was told that I filled out the incorrect form on this page: https://repair.dji.com/us/repair/replacement.  She said this only applies if it was purchased directly through the DJI website.  She instead directed me to this form to fill out: https://repair.dji.com/us/repair/index... or I could use my DJI Care Refresh if I was in a hurry.  I'm definitely going to send it back if I can't resolve the issue... I just thought I would post here to see if there are any other suggestions to save me time from having to ship it out and having to wait a few weeks or so to get it back.  I'm planning on bringing this drone to Fiji this coming August so I have a few months.  

DJI Paladin Posted at 5-28 18:48
Hi there, we apologize for any inconvenience caused by this issue. The propulsion motor of the Mini Series is designed with a spherical bearing. During transportation and storage, the bearing may move within the motor, which leads to the issue you reported. As the spherical bearing cone can be manually adjusted, you can manually rotate the motor to fix this issue. Please power off your drone, and manually rotate the stuck motor. Thank you for your understanding and support.

This is kinda odd since it was working fine during the 9 days out of the box.  I've tried manually rotating and so far it's still stiff versus the other 3 motors.  I'm just waiting for canned air that I purchase to see if this helps out.  

I have got hold of some motors, some have been in salt water, some just hard to rotate, to investigate what is wrong with them, as well as experimented with different ball bearings in steel and all ceramic.
Working on rewriting software for an esp32-c3 to measure current draw, rpm, lift and vibrations. I hope to finish it in the autumn, as I am in a learning process on this processor.

But one thing I found out after testing the engine that was stuck, there were no fragments in them, but the grease in the ball bearing and the lower slide bearing was very thick/hardened, so the oil fixed it on this engine as well.

The oil I have used is 1up Racing Clear Bearing Oil - 8ml

EDIT
The tester is based on this dynamic propeller balancer, with some modifications

Dynamic Propeller Balanser build.
Dynamic Motor and Prop Balancer
.

I don't know how DJI did it, but when I warmed up the motor, it released something inside and blocked the bearing. The mechanical resistance increased a lot. It looked like some kind of security. I haven't encountered this in the mini 2, and I disassemble these motors and replace the bearings.

djiuser_lzpB4pvZYzG4 Posted at 5-28 19:38
This is kinda odd since it was working fine during the 9 days out of the box.  I've tried manually rotating and so far it's still stiff versus the other 3 motors.  I'm just waiting for canned air that I purchase to see if this helps out.

Thank you for keeping us posted. If the issue persists after the said troubleshooting, I'm afraid that you may consider sending your unit in for a proper diagnosis. You may submit a ticket case at https://repair.dji.com/repair/index . Also, the warranty can be applied depending on the outcome of the damage assessment including the warranty period of your unit. Thank you for your understanding and support.

Aurgelme Posted at 5-28 23:56
I have got hold of some motors, some have been in salt water, some just hard to rotate, to investigate what is wrong with them, as well as experimented with different ball bearings in steel and all ceramic.
Working on rewriting software for an esp32-c3 to measure current draw, rpm, lift and vibrations. I hope to finish it in the autumn, as I am in a learning process on this processor.

I will try that, I appreciate it.  

djiuser_lzpB4pvZYzG4 Posted at 5-28 19:36
I spoke to a DJI rep over the phone and was told that I filled out the incorrect form on this page: https://repair.dji.com/us/repair/replacement.  She said this only applies if it was purchased directly through the DJI website.  She instead directed me to this form to fill out: https://repair.dji.com/us/repair/index... or I could use my DJI Care Refresh if I was in a hurry.  I'm definitely going to send it back if I can't resolve the issue... I just thought I would post here to see if there are any other suggestions to save me time from having to ship it out and having to wait a few weeks or so to get it back.  I'm planning on bringing this drone to Fiji this coming August so I have a few months.

I found this in the threads. Mine was doing the same thing. When I did what it said and rotated it by hand it freed up and worked fine. It’s happened a couple of times since after leaving it in the trunk and driving on bumpy roads but once I free it up I don’t have any issues at all with it. Hope this helps.

djiuser_lzpB4pvZYzG4 Posted at 5-28 19:36
I spoke to a DJI rep over the phone and was told that I filled out the incorrect form on this page: https://repair.dji.com/us/repair/replacement.  She said this only applies if it was purchased directly through the DJI website.  She instead directed me to this form to fill out: https://repair.dji.com/us/repair/index... or I could use my DJI Care Refresh if I was in a hurry.  I'm definitely going to send it back if I can't resolve the issue... I just thought I would post here to see if there are any other suggestions to save me time from having to ship it out and having to wait a few weeks or so to get it back.  I'm planning on bringing this drone to Fiji this coming August so I have a few months.

I found this in the threads. Mine was doing the same thing. When I did what it said and rotated it by hand it freed up and worked fine. It’s happened a couple of times since after leaving it in the trunk and driving on bumpy roads but once I free it up I don’t have any issues at all with it. Hope this helps.

Don’t know how I did that twice! My apologies…