ESC diagnoses

[AirScooter]

I have a Mavic Pro that has as part of it's complaints the "ESC Status Unknown" error. I have the leg and motor off and over to a buddy's place who has a variable output power source. His goal is to determine if the motor seems like it is running and excepting inputs as it should.
I have undertaken the job of determining if the legs ESC is functional. I have an idea of how to go about that task, but would really like to hear from someone who has done this kind of thing before. So here is my question:
What is the step by step proper way to diagnose the fault, if any, of a single ESC on the AIO board of the Mavic Pro (2018). Go 4 reports that the fault is on No 2, which I interpret to mean the front left arm and motor and it's corresponding ESC.
Help Please,
AirScooter

 

[The Editor]

I have a Mavic Pro that has as part of it's complaints the "ESC Status Unknown" error. I have the leg and motor off and over to a buddy's place who has a variable output power source. His goal is to determine if the motor seems like it is running and excepting inputs as it should.
I have undertaken the job of determining if the legs ESC is functional. I have an idea of how to go about that task, but would really like to hear from someone who has done this kind of thing before. So here is my question:
What is the step by step proper way to diagnose the fault, if any, of a single ESC on the AIO board of the Mavic Pro (2018). Go 4 reports that the fault is on No 2, which I interpret to mean the front left arm and motor and it's corresponding ESC.
Help Please,
AirScooter

Afraid there is no easy way to test/diagnose an esc (Other than possibly open circuit FETS).

DJI use sine wave driven esc’s that utilize back emf for braking the motors which makes them a little more complex than ‘standard’ modules. The motors themselves are driven by a varying pulse width modulated square wave output which is what enables the speed control.

 

[RadioFlyerMan]

This may not help, but here's my shot in the dark. I connect the AC to Assistant 2 in debug mode. Then test the motors via the Basic Settings. Each button (M1, M2 etc) turns the respective motor. There is an ESC Calibration, but I did not mess with it because I don't know what I'm doing. ???

 

[AirScooter]

Very good reply RFM,
I'm going to try it, but before I do, I'm wondering what the reporting screen would indicate if one of the ESC's were dead?
If I could prove to myself that one was dead then I would start cutting back on dog food. This old mutt needs to go on a diet anyway.
Thanks RFM great comeback.
AirScooter

 

[AirScooter]

This may not help, but here's my shot in the dark. I connect the AC to Assistant 2 in debug mode. Then test the motors via the Basic Settings. Each button (M1, M2 etc) turns the respective motor. There is an ESC Calibration, but I did not mess with it because I don't know what I'm doing. ???

View attachment 94387

Very good reply RFM,
I'm going to try it, but before I do, I'm wondering what the reporting screen would indicate if one of the ESC's were dead?
If I could prove to myself that one was dead then I would start cutting back on dog food. This old mutt needs to go on a diet anyway.
Thanks RFM great comeback.
AirScooter

Very good reply RFM,
I'm going to try it, but before I do, I'm wondering what the reporting screen would indicate if one of the ESC's were dead?
If I could prove to myself that one was dead then I would start cutting back on dog food. This old mutt needs to go on a diet anyway.
Thanks RFM great comeback.
AirScooter

RFM,
Here is the follow through I promised last week, which feels to me like a month of Sundays. I have been living with this drones electronics night and day and have finally come to the conclusion that if I could buy a board cheap enough I would. I found one last night, $68 USD, and it will arrive Thursday of this week.
Here's what I learned. Being as stupid as I am almost anything creates a learning opportunity:

1. It takes very little in the way of heat, water, impact to turn the boards in the Mavic into "For Parts Only" kings and queens. Really when you think about it the human body is not very much more robust. There a lot organic in the Mavic.

2. DJI has far too firm a grip on the parts availability and proprietary nature of same. Finding parts to repair almost anything below the component level is next to impossible.
Case in point:
I think its reasonable to assume that the ESC's in the Mavic Pro are fairly common. DJI buys and applies so many of them that it is easy to ask their suppliers to Laser Etch their name and part number on their face. This pretty much stops any hope of aftermarket sourcing of individual chips. This unhappy circumstance is then compounded by the inappropriately priced components, boards in this case, available for the consumer.

3, There is something pretty incestual about how DJI interacts with the Chinese manufacturing sector. I will ask just this one question for clarity and then I'll stop: Has anyone who haunts these posts ever known the usually voracious Chinese manufacturing sector to leave any product as successful. as the DJI products generally are, totally uncloned? I know there are a million knockoffs, but no real clones either in the form of electronic parts or of entire systems. Autel probably comes closest. but its my guess that DJI will buy Autel shortly (if they haven't done so already) as a means of deigning that segment of the market to any competition.

I'm glad of the opportunity to get that off my chest .....
AirScooter

 

[lee82gx]

I had a similar experience for my own Mavic Air. ESC status error, unknown if the motors or ESC fault or both.

One thing I tried was a basic continuity check of each of the coils on the motor. It showed a broken coil at the black wire, over stretched due to arm over bend and crash. When I re-striped the good section of the black coil and resoldered the black wire to the ESC, all was good.

Another way to know which particular motor or channel is definitely the tell tale small shake or turn when power on. At least that isolates which channel is faulty. If you have both ESC and Motor at fault I guess it'll be very difficult to properly diagnose without external systems like your friend's variable output or another good part.

FWIW if I was DJI, this is exactly how I'd design and manufacture and sell my products - as many lock ins as possible so that there will be no splicing of my products with others. It guarantees a monopoly and that guarantees good profit. In return they try to give you the best overall product (as attested by your purchase) for the money.

Another good reason for locking in the subcomponents is the fact that these are aircraft with spinning propellers. By themselves they can generate quite a bit of harm to any living thing. No big company will want any bad publicity from unchecked usage.

 

[thenohup]

This may not help, but here's my shot in the dark. I connect the AC to Assistant 2 in debug mode. Then test the motors via the Basic Settings. Each button (M1, M2 etc) turns the respective motor. There is an ESC Calibration, but I did not mess with it because I don't know what I'm doing. ???

View attachment 94387

Hello Does the diagram applies to Mavic 2 Pro?
I am getting ESC 3 and 4 errors. I am looking at diagnosing and fixing it myself.
In addition, why am I not getting those options on the left just Firmware update, Flight Data, Calibration and Simulator only?

Thanks!