Yesterday I had my first motor speed error. Based on graph from hovering test, the wings from front right motor needs to be replaced?

I have replaced it. Much better now

Tommy76_86 Posted at 6-7 06:06
[view_image]

Yesterday I had my first motor speed error. Based on graph from hovering test, the wings from front right motor needs to be replaced?

The Motor Speed Error message tells you which propeller blades need to be replaced.  When you land the Mini the motor will be identified by the beeping ESC.


This is what the beeping ESC looked and sounded like when my left-rear prop blades were flagged by the Motor Speed Error message.

  

I have had my mini since January, took it to the Virgin Islands in the flymore case and never had any problems. Did the firmware update and now almost every time I fly I got the message. Bought some more props and I updated the firmware for the other two batteries and today all was good even in considerable wind. I am also being extra careful about putting it in the case. Hope I am good although it doesn't seem to make sense that the battery firmware would have anything to do with it.

I have had my mini since January, took it to the Virgin Islands in the flymore case and never had any problems. Did the firmware update and now almost every time I fly I got the message. Bought some more props and I updated the firmware for the other two batteries and today all was good even in considerable wind. I am also being extra careful about putting it in the case. Hope I am good although it doesn't seem to make sense that the battery firmware would have anything to do with it.

hallmark007 Posted at 6-5 15:42
That’s a pity, because mini is a real good drone and flying better than it ever did, but to many people trying to create problems that are not there, by continually trying to steer what is a small SW problem down the unnecessary road of claiming it’s  HW.

Mavic Craig Posted at 6-4 18:47
I am having the same issue with my MM. First flight in a little while I get the Motor Speed Error notification. Returned home replaced the indicated propeller with brand new ones and still received the same error. I do have the Fly More combo and store my drone in the case. The props are straight and unmarked. I'm thinking it's a firmware issue. It appears that it is a common issue DJI.

Okay. Updated firmware via Windows 10 and DJI Assistant 2. All was successful. All three batteries and MM. Same new propellers and same issue during the three minute flight. "Motor speed error" left rear motor. Something is NOT right.

I had the same issue as most here.  2-week old drone and after an hour of good flight time, I got this error.  I replaced all of the props and screws according to their tutorial and got the same error.  I ended up contacting support and shipping it back to them.  After a few weeks, they ended up repairing it.  The email stated that the "Power ESC Board Module" was replaced but when I got the drone it appeared to be an entirely new one (The drone I shipped them had a decal/skin kit on it and the one I received appeared to be packaged like it was brand new without the skin).

Thinking outside of the box...

What if it wasn't the prop, but for some reasons a structural  weakness of the back left leg, providing the wrong angle to the prop ?

That would be consistent with the fact that even when swapping props, alert msg pops up about the same place.

philgib Posted at 6-8 13:09
Thinking outside of the box...

What if it wasn't the prop, but for some reasons a structural  weakness of the back left leg, providing the wrong angle to the prop ?

Wouldn't explain the elevated motor RPM's seen with bad prop, and after replacing bad prop with a good prop, motor RPM's lower down closer to RPMs of other three motors.

It would however add another cause for ESC problem.

Mavic Craig Posted at 6-7 23:50
Okay. Updated firmware via Windows 10 and DJI Assistant 2. All was successful. All three batteries and MM. Same new propellers and same issue during the three minute flight. "Motor speed error" left rear motor. Something is NOT right.

Did you store your MM in DJI case after having replaced old props with new props?

Just adding to the group: same issue. Left rear prop here as well.

I also just had the left rear motor issue on a 3 week old MM. I have thew fly more combo so I replaced the props, but when I did the indoor hover test and checked the DAT file my right rear prop was also showing elevated RPMs in the 11-12k range, versus ~9500 RPM for the front props. I've read a bunch of threads on this and I'm unsure how to store the MM in the fly more case to avoid this from happening again- can it be safely stored in the case if the props are facing each other, or are the props getting damaged no matter how it's store in the case? I wasn't as careful with storing the MM in the case earlier, so the rear props may have been deformed by the bottom of the case during storage. I'm worried about that now, so I want to make sure I store it in the case correctly.

The alert msg pops up at the exact moment of the first time I descend during the flight. Is that the case for everyone ?

I've attached the DAT files from before and after I changed my left rear prop. It looks like changing the prop did improve the situation, as the indoor hover RPMs are back down below 10k for the left rear motor. The right rear motor is stil elevated so I may change the props on that motor too. I haven't tried flying it out doors to se if I get the motor speed warning again.

Maybe one of pi....d off users will send his drone to  for example Federal Aerospace Administration (or other equivalent agency in other country) to investigate potential unsafe flying object. Maybe this could make producer a more interested in internal investigation how it is possible that dozens of users demolish brand new propellers on one specific wing of drone which most of air operations including sensitive ones (starting and landing) performs almost automatically with minimum interference of pilot. I don't know but in my childhood sometimes the soultion was to ask bigger and stronger for help

dubtastic Posted at 6-8 06:34
I had the same issue as most here.  2-week old drone and after an hour of good flight time, I got this error.  I replaced all of the props and screws according to their tutorial and got the same error.  I ended up contacting support and shipping it back to them.  After a few weeks, they ended up repairing it.  The email stated that the "Power ESC Board Module" was replaced but when I got the drone it appeared to be an entirely new one (The drone I shipped them had a decal/skin kit on it and the one I received appeared to be packaged like it was brand new without the skin).

It’s normal to receive a new drone, but most likely your drone was tested and as a result of test diagnosis was ESC problem.

There is much rubbish surrounding props, but dji have put notice on this thread as to what could be wrong and what to do. But to many interfering trying to make some more out of this than has been posted by dji.

Flat props, wing tips flattened out. This was complete horse sh*t as we all know that all dji drones up to and including Mavic Air had completely flat wing tips and craft flew fine.

Props with wing tips curled up where designed to lower noise of prop first seen in Mavic pro platinum and made available for orignal Mavic . So we had perfectly straight props with no wing tips curled and also props with wing tips curled and both sets had no great difficulty in flying craft and neither had better results than the other.

Now All phantoms up to P4pro had “flat props” all inspire matrice Mavic pro and Mavic air, so the amount of BS being spread by a few who forgot to mention this to others or who actually forgot it altogether, I’ve seen so many posts showing these wing tips slightly flattened out and users being told somehow these props will cause major problems with their drone and that was utter rubbish and failed to mention that many drones fly perfectly well with similar props.

What most people reading through most of the BS here is, hover test can show a different result every time you run it, it can show different result outside as it does inside, it will show a different result every week. And the only purpose of doing it is to try to tune props to the way you think you need them. It’s not for testing bad props bad props don’t need testing you can see bad or damaged props and if warning tells you prop is bad, do what dji ask above and if your prop looks fine then it most likely is, some like you have returned some have just changed prop and some have just refreshed FW and a very few have tried hover test then changed props.

To much BS about this I think follow dji instructions at the top of this thread...

tTownTom Posted at 6-9 02:24
Just adding to the group: same issue. Left rear prop here as well.

Likely result of following DJI's instructions as to how to position props for storage.
Reverse which rear prop goes over vs. under, and problem will switch to Right rear prop.

HedgeTrimmer Posted at 6-10 16:19
Likely result of following DJI's instructions as to how to position props for storage.
Reverse which rear prop goes over vs. under, and problem will switch to Right rear prop.

What is the safest way to store it in the fly more case if not with the props aligned?

rhainman Posted at 6-11 04:59
What is the safest way to store it in the fly more case if not with the props aligned?

Here you go.

rhainman Posted at 6-11 04:59
What is the safest way to store it in the fly more case if not with the props aligned?

Believe safest way to store Mavic Mini comes from forum member Zbip57.
3rd Party Case where blades are stored in line with body of Mavic Mini instead of across body.

See Zbip57's post here.



Wouldn't need to be this particular case.  Something similar which does not require Tips of rear blades being pushed under Body of rear blades on opposite side.

Having sufficient room, you might consider storing Mavic Mini in a cabinet with out blades folded.  

Mavic Craig Posted at 6-7 23:50
Okay. Updated firmware via Windows 10 and DJI Assistant 2. All was successful. All three batteries and MM. Same new propellers and same issue during the three minute flight. "Motor speed error" left rear motor. Something is NOT right.

Since you eliminated possibility unsuccessful .500 firmware install, and you are still getting .500 warning about "Motor speed error" left rear motor.

Have you tried replacing Left Rear prop (with a new matched set of blades)?

Have you tried suggested Hover test and looking at RPM speeds of all four motors?

Zbip57 Posted at 6-7 14:35
The Motor Speed Error message tells you which propeller blades need to be replaced.  When you land the Mini the motor will be identified by the beeping ESC.

Please remember that the opposite blades must also be replaced, even if only one ECS sound! Note the description on the packaging!

Satstream Posted at 6-12 00:41
Please remember that the opposite blades must also be replaced, even if only one ECS sound! Note the description on the packaging!

You need to replace both blades on the beeping motor, that's it. You do not have to replace the blades on the opposite (diagonal) motor, if that motor is not beeping.

rhainman Posted at 6-9 09:11
[view_image]I've attached the DAT files from before and after I changed my left rear prop. It looks like changing the prop did improve the situation, as the indoor hover RPMs are back down below 10k for the left rear motor. The right rear motor is stil elevated so I may change the props on that motor too. I haven't tried flying it out doors to se if I get the motor speed warning again.

Your test shows why some of us keep recommending the hover test, as a way to confirm whether you really need to replace the props or not. Your first chart shows very clearly that both rear motors were spinning way too fast for a hover, with the RightRear being well over 11k RPMs. You replaced the props on that corner, and your RPMs went down dramatically.  I would definitely replace the LeftRear props too, as that motor is also spinning too fast. Your MM will thank you for it.

rhain.louis@gmail.com Posted at 6-9 07:57
I also just had the left rear motor issue on a 3 week old MM. I have thew fly more combo so I replaced the props, but when I did the indoor hover test and checked the DAT file my right rear prop was also showing elevated RPMs in the 11-12k range, versus ~9500 RPM for the front props. I've read a bunch of threads on this and I'm unsure how to store the MM in the fly more case to avoid this from happening again- can it be safely stored in the case if the props are facing each other, or are the props getting damaged no matter how it's store in the case? I wasn't as careful with storing the MM in the case earlier, so the rear props may have been deformed by the bottom of the case during storage. I'm worried about that now, so I want to make sure I store it in the case correctly.

If your Right Rear motor is hovering in the 11-12k RPM range, I would replace the props.
DJI responded to a MM owner with some motor specs, where hovering speed was listed at 10200 RPMs, but they didn't say if that's an average value, or if it should be considered an upper limit. In any case, we have seen numbers as low as 9400 RPMs with brand new props, so - in my personal opinion - 11-12k is too high. Replace, do the test again, and see for yourself if that helped or not.

120ccpm Posted at 6-12 16:24
You need to replace both blades on the beeping motor, that's it. You do not have to replace the blades on the opposite (diagonal) motor, if that motor is not beeping.

I didn't write diagonally! Motorspeed error came on the right rear of the mavic mini, first I replaced these props! After the restart, again Motorspeed error, this time in the back left ... exchanged, all good.

Exchanged both props at the back, upgraded again with 1.05 from my Android phone. Everything is ok .
But I will add custom prop protections before placing it into the box again.

I am pretty sure the box is responsible for the issue, where the back props are. At rest in the box, there is too much space between the arm and the props, meaning a lot of potential for the props to lose its shape, as the MM is literally resting on the back props.
So we should design in 3D some spacer to fit between the arm and the props, preventing the props for resting and not bending. That is, at rest obviously, not in flight ;-)

philgib Posted at 6-13 23:10
Exchanged both props at the back, upgraded again with 1.05 from my Android phone. Everythind is ok . I will add custom prop protections before placing it into the box again. I am pretty sure the box is responsible for the issue, where the back props are.

Your guess is correct! My Mavic mini was in the transport box for about 12 days, after a test flight, the motorspeed error came on the back right after a few seconds. No accidents or abnormalities before! So when stowing in the transport box you have to pay special attention to the rear props!

Satstream Posted at 6-13 02:03
I didn't write diagonally! Motorspeed error came on the right rear of the mavic mini, first I replaced these props! After the restart, again Motorspeed error, this time in the back left ... exchanged, all good.

Your recommendation to replace the props on more than one motor, when you get the Motor Speed Error, is incorrect regardless of what you meant with "opposite". In your specific case, you got the error on one motor, replaced the props and got another error on another motor, but you cannot turn that into a general rule. Several people got the error on one motor, replaced the props there, and that was it.
If you want to see how your props are performing, do the hover test and look at the motor speeds.

I've just opened my brand new MM (Fly more combo). Just look at the rear props, both left and right they are not just bended but their edges are deformed. Haven't started the drone yet but no wonder that I will get the error as soon as it will take off. It's for sure this is the reason why others with brand new MMs have the same issue. So probably my first move should be the replacement of the props, of course on my own expense :-(.

edge2

edge1

If I understood correctly the function of checking the motor speeds and in case of an anomaly issuing a warning has been introduced in the new FW and therefore just getting an error message is the novelty.  So this is just the effect of the changed motor speed and this was present in the past to. As a rookie I would like to ask those members who have his drone for a long time if they had any problem because of this. Did you have problems with the motors, they needed to be replaced?

DJI should have a replacement program to replace the props and/or case... I bought the fly more package for the case and now it's useless because I dont want to further damage the props. I've only had the mavic mini for less than 3 months and already replaced two props.....

lporsche Posted at 6-16 06:26
If I understood correctly the function of checking the motor speeds and in case of an anomaly issuing a warning has been introduced in the new FW and therefore just getting an error message is the novelty.  So this is just the effect of the changed motor speed and this was present in the past to. As a rookie I would like to ask those members who have his drone for a long time if they had any problem because of this. Did you have problems with the motors, they needed to be replaced?

Replace the propeller blades, not the motors.

lporsche Posted at 6-16 06:17
I've just opened my brand new MM (Fly more combo). Just look at the rear props, both left and right they are not just bended but their edges are deformed. Haven't started the drone yet but no wonder that I will get the error as soon as it will take off. It's for sure this is the reason why others with brand new MMs have the same issue. So probably my first move should be the replacement of the props, of course on my own expense :-(.
[view_image][view_image][view_image]

While that small dent looks bad, it might actually have no tangible impact. We have seen props with dents and scratches perform better (i.e. providing more lift) than props that looked like new. You can either do the hover test to see what's going on with your props, or you can take the other approach and wait for the Motor Speed Error to appear. You can also try to straighten that dent out, by hand.

lporsche Posted at 6-16 06:26
If I understood correctly the function of checking the motor speeds and in case of an anomaly issuing a warning has been introduced in the new FW and therefore just getting an error message is the novelty.  So this is just the effect of the changed motor speed and this was present in the past to. As a rookie I would like to ask those members who have his drone for a long time if they had any problem because of this. Did you have problems with the motors, they needed to be replaced?

Testing the motor speeds with the hover test will give you an idea of how your props are actually performing.  It's not a real-world stress test of course, but it's simple, repeatable and provides rather useful insights. Normal values are in the 9500-10000 range... the higher you go, the higher the likelihood you will hit the threshold that triggers the Motor Speed Error (which has been introduced in the latest firmware).
I have seen no reports of failing motors. It's possible that constantly higher RPMs will have a negative impact on their longevity, but it might very well be negligible, as the overall increase in RPMs is limited.

120ccpm Posted at 6-16 11:28
While that small dent looks bad, it might actually have no tangible impact. We have seen props with dents and scratches perform better (i.e. providing more lift) than props that looked like new. You can either do the hover test to see what's going on with your props, or you can take the other approach and wait for the Motor Speed Error to appear. You can also try to straighten that dent out, by hand.

Yesterday evening I took the MM to our maiden flight and it seems that you were right, those bents haven't caused any problem. I flew twice, once for 7 and the second time for 16 minutes - it's true that I flew mainly in C mode - but i didn't get any error message. I used two different batteries for which I made the FW update.

Zbip57 Posted at 6-16 09:37
Replace the propeller blades, not the motors.

I asked the question because if there were no reported motor failures (breakdowns) - and my previous remark that the problem existed ever since the MM was launched it's correct - than I think that even if it's not normal, the motors can handle this overload without causing a problem. Therefor a temporary solution would be to downgrade the FW back to version 1.00.0400 until this will be sorted out by DJI and getting a better solution. Although if this is happening mainly in rear left motors and the props shape and/or condition is just one factor of the problem that I think there's no solution for this just to remove this alarm function from the next FW and keep fingers crossed.

messages started on the very first flight after the firmware update...first started getting "motor speed error"....changed the beeping prop (rear left one) and also the rear right one...was ok for the next two flights...started getting "propeller rotating too fast" messages...changed all four props sets (the ones I changed two flights ago aswell)...got up in the air - "propeller rotating too fast" again...extra carefull with the fly more case, extra carefull with the drone handling...this has to be a firmware update problem!  Changing the props doesn't solve the problems! DJI, when can we expect the next firmware update? This is really frustrating...

lporsche Posted at 6-16 22:01
I asked the question because if there were no reported motor failures (breakdowns) - and my previous remark that the problem existed ever since the MM was launched it's correct - than I think that even if it's not normal, the motors can handle this overload without causing a problem. Therefor a temporary solution would be to downgrade the FW back to version 1.00.0400 until this will be sorted out by DJI and getting a better solution. Although if this is happening mainly in rear left motors and the props shape and/or condition is just one factor of the problem that I think there's no solution for this just to remove this alarm function from the next FW and keep fingers crossed.

Yes, the problem has existed ever since the Mavic Mini was launched.  The issue is prop deformation creating a loss of lift.  The Mini compensates by spinning the motor faster to generate the required amount of lift.  Eventually the motor reaches a point where it is unable to spin any faster.  Without sufficient lift the Mini will descend uncontrollably.

DJI added warning messages to their firmware, like Max Power Reached, or the latest Motor Speed Error.  Downgrading to a previous firmware version will remove the 1.00.0500 Motor Speed Error message, but it will not cure the underlying issue which is triggering that warning.  


"Keep fingers crossed" is not a realistic solution, neither is being "extra carefull with the fly more case".

I posted graphs and photos documenting the difference in performance between deformed props that triggered a Motor Speed Error warning versus a fresh set of new propeller blades.  Even though a cursory visual inspection showed no apparent difference between the old vs new blades, the data plots demonstrate a very clear difference.

Check out posts #903-916 on pg 23 of this thread.  MOTOR SPEED ERROR AFTER  04/2020 FIRMWARE

For a suggestion on how to avoid deformation on your next set of propeller blades, see also posts #922-929 on pg 24 of the same thread.