Motor Current Error

[AndyJC]

Hi folks.

I'm getting the above error every time I fly my Mavic Pro which I purchased last week (used but appeared immaculate).
Wondering if anyone would mind checking my flight data to see if they can work out which motor is causing the error, assuming it is a motor and not something else.

Template filled in below....

Problem?
Getting "motor current error. Check your propellers and fly with caution" on every flight, as soon as I take off.

Was unit in a crash?
Not that I know of(purchased used last week but looks new and had around 2hrs previous fly time)

What have you tried so far?
Change all 4 probs to new. Both sets original DJI.
Inspected and cleaned motors with camera air blower
Checked motors for damage and constant rotation. All perfect.
Factory reset drone
Rolled back to previous firmware then back to current.
Calibrated IMU and compass numerous times.
Calibrated sensors

What device are you using ( iphone , ipad, Samsung , etc)?
Galaxy S10

What firmware are you running ( aircraft, remote controller)?
01.04.0500

What Go app version are you using?
4.3.32

Any modification? (if so what)
N/A

Did you change anything or install any apps? (if so what)
No
Do you have a video or pictures of the problem? (if so post link)
Have a screen record but it only shows the error showing within a few seconds.

It happens in normal and sport mode, even if I take off as gently as I can. Temperature is around 7c. Wind or no wind doesn't seem to make a difference either.

Many thanks in advance ??

 

[slup]

Hi there, welcome to the forum.

I would bet on something not good with the left front ... look at the current draw, that motor differs quite a bit from the other three. Same story from both DAT logs. (By the way ... the 2 TXT logs comes from a Mini?)

DAT70


DAT71

 

[AndyJC]

Oh wow, thank you so much!

That's really interesting. Is it possible the motor could be problematic without being physically damaged? There aren't any signs of damage but I've not owned it since new so couldn't be ruled out.

I'm prepared to swap the arm out myself if that's definitely where the issue is. Could this problem be caused by anything else (like ESC board) or do you think it's worth taking a chance and swapping the leg out?

Sorry about posting the wrong txt files. I had a Mini until last week when I sold it to buy the pro!?

 

[slup]

Oh wow, thank you so much!

That's really interesting. Is it possible the motor could be problematic without being physically damaged? There aren't any signs of damage but I've not owned it since new so couldn't be ruled out.

I'm prepared to swap the arm out myself if that's definitely where the issue is. Could this problem be caused by anything else (like ESC board) or do you think it's worth taking a chance and swapping the leg out?

Sorry about posting the wrong txt files. I had a Mini until last week when I sold it to buy the pro!?

Perhaps a slightly bent prop shaft ... can you see any signs of vibration or wobble from that motor when up & running?

Don't think it's a Prop defect there as the RPM's were similar for all 4 ...

 

[AndyJC]

@slup If you don't mind me asking, what tool did you use for reading the motor current logs, is it the paid version of Airdata?

 

[slup]

No, nothing paid, it's CsvView, get it here --> CsvView Downloads

Then unfortunately something popped up in the back of my mind regarding just the current data in the log for the front left motor ...
They might not be completely true ... read in below thread & 2 posts below were @BudWalker, the creator of CsvView points this out.

Mavic Mini Lost in the Ocean

Perhaps we took a giant step back to square one

But don't give up ... below current graphs is from a M2P, my own MA & another MP, they doesn't show anything strange with the Left front current data. Let's see if @BudWalker have time to shime in & explain once that side of the Atlantic wakes up.

M2P


MA


Another MP

 

[BudWalker]

No, nothing paid, it's CsvView, get it here --> CsvView Downloads

Then unfortunately something popped up in the back of my mind regarding just the current data in the log for the front left motor ...
They might not be completely true ... read in below thread & 2 posts below were @BudWalker, the creator of CsvView points this out.

Mavic Mini Lost in the Ocean

Perhaps we took a giant step back to square one

But don't give up ... below current graphs is from a M2P, my own MA & another MP, they doesn't show anything strange with the Left front current data. Let's see if @BudWalker have time to shime in & explain once that side of the Atlantic wakes up.

M2P
View attachment 94632

MA
View attachment 94633

Another MP
View attachment 94634

It's just the MavicMini .DAT that has problems with the motor currents. So the observations you've made about this MP are correct.

I would only add that the left front motor speed and motor commanded are similar to the other motors. It doesn't have to turn faster so the prop is OK. And, it doesn't have to be commanded higher so a motor obstruction is unlikely.

 

[AndyJC]

@BudWalker @slup so with your diagnosis in mind, do you think it's worth taking a chance and replacing the front left arm?

I can confirm that I've swapped the props out with new and there's no noticeable resistance in the front left so the points you make BudWalker make sense.

Thank you both for you help so far, it's greatly appreciated ?

I've spent days tring to get to the bottom of this and, as you can imagine, it's heart breaking buying a new(to me) drone but not being able to fly it. It's nice to know I may be making some headway!

 

[slup]

...I would only add that the left front motor speed and motor commanded are similar to the other motors. It doesn't have to turn faster so the prop is OK. And, it doesn't have to be commanded higher so a motor obstruction is unlikely...

Yeah ... that's a correct observation. Hmm ... have looked through all motor related signals & can only find a big deviation among the motors when it comes to the current.
Can it be as simple as a bad motor cable connection somewhere out to the left front motor..?

@BudWalker ... do you know the meaning of the signal group "esc_data", it's only there I again find big deviations for one of the 1-4 numbered signals ... that with number 4 which could mean one of the motors. Thinking if this could be the next level ... closer to the error source?

Signals were #4 deviate quite a lot from the rest ...

 

[BudWalker]

Yeah ... that's a correct observation. Hmm ... have looked through all motor related signals & can only find a big deviation among the motors when it comes to the current.
Can it be as simple as a bad motor cable connection somewhere out to the left front motor..?

@BudWalker ... do you know the meaning of the signal group "esc_data", it's only there I again find big deviations for one of the 1-4 numbered signals ... that with number 4 which could mean one of the motors. Thinking if this could be the next level ... closer to the error source?

Signals were #4 deviate quite a lot from the rest ...

View attachment 94667

View attachment 94668

View attachment 94669

View attachment 94670

The esc_data is the same as the Motor data. Except in cases like this. The .DAT has information that defines the contents of each of the particular record types. But, the recDefs are spread throughout the .DAT. Since these .DATs were relatively short the esc_data wasn't fully defined. In addition, the esc_data recDef was towards the end of the .DAT and several lines got lost due to corrupted data that often occurs at the end.

Many of these "DatDefined" data have been "Engineered" by scaling, if necessary, and assigning more understandable labels. In addition, derived data has been added to some of the Engineered records.

You can choose which data you want to see by directing CsvView/DatCon like this


BTW, if you had chosen Engineered then DatDefined DatCon/CsvView would have been satisfied with the Engineered Motor recDef and would've not also given you the DatDefined esc_data record

DatCon/CsvView could be made smarter and reject the DatDefined esc_data recDef for cases like this. I've left it loose for cases where the DatDefined recDef is all there is and could possibly provide some benefit. I'll probably change that.

You can see what these definitions look like by directing DatCon like this.

 

[BudWalker]

Oh wow, thank you so much!

That's really interesting. Is it possible the motor could be problematic without being physically damaged? There aren't any signs of damage but I've not owned it since new so couldn't be ruled out.

I'm prepared to swap the arm out myself if that's definitely where the issue is. Could this problem be caused by anything else (like ESC board) or do you think it's worth taking a chance and swapping the leg out?

Sorry about posting the wrong txt files. I had a Mini until last week when I sold it to buy the pro!?

I would guess it's a sensor or wiring problem. I.e. the leftFront isn't really pulling that many amps. The total current drain on the battery should be about 1 amp greater than the sum of the motor currents. Here the total current is less than the leftFront motor current.


Why do you want to replace the leftFront arm?

 

[AndyJC]

@BudWalker in the hope that the problem would be fixed I guess.

I'm getting the 'motor current error' every time I take off so want to try and get to the source of problem and fix it, if I can.

If you don't think replacing the motor will help, which direction do you think I should go in? Replace ESC board possibly?

 

[slup]

The esc_data is the same as the Motor data. Except in cases like this. The .DAT has information that defines the contents of each of the particular record types. But, the recDefs are spread throughout the .DAT. Since these .DATs were relatively short the esc_data wasn't fully defined. In addition, the esc_data recDef was towards the end of the .DAT and several lines got lost due to corrupted data that often occurs at the end.

Many of these "DatDefined" data have been "Engineered" by scaling, if necessary, and assigning more understandable labels. In addition, derived data has been added to some of the Engineered records.

You can choose which data you want to see by directing CsvView/DatCon like this
View attachment 94673

BTW, if you had chosen Engineered then DatDefined DatCon/CsvView would have been satisfied with the Engineered Motor recDef and would've not also given you the DatDefined esc_data record

DatCon/CsvView could be made smarter and reject the DatDefined esc_data recDef for cases like this. I've left it loose for cases where the DatDefined recDef is all there is and could possibly provide some benefit. I'll probably change that.

You can see what these definitions look like by directing DatCon like this.
View attachment 94672

Thank's for taking the time to explain @BudWalker ... with time I perhaps will get around all info you gave me, for now I'm just stockpiling all pieces of info for a hopeful near future understanding. Right now I at least know that it's a lot of data in the logs.. of which probably only a fraction is understandable, for me at least

@AndyJC ... I'm afraid that this is as far I can come without mechanically digging into your MP myself, good luck with your search

 

[BudWalker]

@BudWalker
If you don't think replacing the motor will help, which direction do you think I should go in? Replace ESC board possibly?

@AndyJC ... I'm afraid that this is as far I can come without mechanically digging into your MP myself, good luck with your search

I'm with @slup on this. Whether you try to fix it or send it off to a DJI repair facility is a choice only you can make.

 

[AndyJC]

@BudWalker @slup Thank you for your help guys, I appreciate it.
I'm the type of person that doesn't usually send things in for repair. As an IT engineer I'm used to working on phones, laptops etc so hoped the MP wouldn't get the better of me.
You guys are clearly very knowledgeable and if you're suggested I need to send it in, maybe it's the only option?

 

[Martysticks]

Hi there, welcome to the forum.

I would bet on something not good with the left front ... look at the current draw, that motor differs quite a bit from the other three. Same story from both DAT logs. (By the way ... the 2 TXT logs comes from a Mini?)

DAT70
View attachment 94617

DAT71
View attachment 94618

What software are using to generate these reports? Looks extremely interesting.

 

[BudWalker]

@BudWalker @slup Thank you for your help guys, I appreciate it.
I'm the type of person that doesn't usually send things in for repair. As an IT engineer I'm used to working on phones, laptops etc so hoped the MP wouldn't get the better of me.
You guys are clearly very knowledgeable and if you're suggested I need to send it in, maybe it's the only option?

You've misunderstood my response. I did not suggest that you need to send it DJI repair. What I said is that you have to make the decision to either fix yourself or send it to DJI.

 

[AndyJC]

@BudWalker @slup Thanks guys.

Went for a couple of short test flights this morning. Got the motor error message after take off both times but once cleared it didn't come back, which it used to.
It actually flys OK so I may see how it goes for a while....

 

[AndyJC]

What software are using to generate these reports? Looks extremely interesting.

@Martysticks
A CSV reading tool created by BudWalker. A link was posted further up by Slup?