Gimbal Misbehaving on startup and calibration

[GaryPHayes]

Been flying this MP1 for a good 2 years (600+ flights), after a care refresh as the previous MP1 which flew fine for over a year, did the same thing.

DJi forum just say send it in and standard repair companies in Australia are likely to charge $200+ just to change a ribbon or something. So, is it worth just getting the ribbon off eBay and doing it myself (reasonably good at electrical repairs), buying a complete housing and replacing it OR send it to 3rd party or DJi?

This is what happens at start up

https://garyphayes.photography/wp-content/video/VID_20200124_163629.mp4

This is what happens on calib (gets to about 50%)

https://garyphayes.photography/wp-content/video/VID_20200124_095452.mp4

Cheers in advance

 

[brett8883]

Been flying this MP1 for a good 2 years (600+ flights), after a care refresh as the previous MP1 which flew fine for over a year, did the same thing.

DJi forum just say send it in and standard repair companies in Australia are likely to charge $200+ just to change a ribbon or something. So, is it worth just getting the ribbon off eBay and doing it myself (reasonably good at electrical repairs), buying a complete housing and replacing it OR send it to 3rd party or DJi?

This is what happens at start up

https://garyphayes.photography/wp-content/video/VID_20200124_163629.mp4

This is what happens on calib (gets to about 50%)

https://garyphayes.photography/wp-content/video/VID_20200124_095452.mp4

Cheers in advance

It’s easy enough to replace the ribbon if you have some electronics repair experience. The only hard part is the ribbon cable is folded up like an origami crane so takes some fooling around to get right. I’d recommend getting a couple as they are cheap.

Yes it’s easier to replace just the housing with the ribbon cable already attached but it’s not necessary.

 

[GaryPHayes]

It’s easy enough to replace the ribbon if you have some electronics repair experience. The only hard part is the ribbon cable is folded up like an origami crane so takes some fooling around to get right. I’d recommend getting a couple as they are cheap.

Yes it’s easier to replace just the housing with the ribbon cable already attached but it’s not necessary.

Thanks Brett - will order in a moment. From what you see re: the odd gimbal behaviour do you think it is the 'usual' slightly damaged ribbon? Or something more PCB ? - from what I have seen it seems a common problem but one never knows ... Best Gary

 

[JamieB]

I had the same issue along with a gimbal motor overload error in the app. Swapping out the ribbon cable solved the problem for me! Like Brett said, it does take some disassembly to get to the gimbal and the cable itself is a bit fiddly to install, but as long as you've got some experience with electronic repair work it's not too complicated. I found this video super helpful:

 

[lookout]

So I bought this Mav Pro used. And it seemed to be okay at first. It flies like glass but the gimbal is another matter. It worked for the first few times and seemed to be solid on the gimbal. Maybe I keep forgetting to remove the shipping tab a few times. All it wants to do is burn itself up. It still flies even after landing upside down; RTH got carried away. But the gimbal just keeps getting worse about shaking. So I tried the whole gimbal calibration. It went to 65% before dropping out. And did it again, and it controlled the camera just fine until it failed calibration for the second time. Now when I run the camera/turn it on, all it wants to do is stick in one place, and shake around up and down to get itself into a place that jams against all motor locks. Maybe I should've left the calibration alone, but I didn't do IMU because it was flying just fine. I can't get it to stop trying to burn the gimbal up. Without power, it seems the motor just wants to lock into one location like something is forcing it to stay in that position.

Nothing useful in Assistant 2 to help me. Go 4 says I have the latest firmware. The error that kept popping up in Go 4 was I need to check the gimbal connection. Gimbal shaking error.

I got to about 51% on another attempt where the gimbal didn't move at all.

The frame and tabs haven't lipped over.

 

[brett8883]

So I bought this Mav Pro used. And it seemed to be okay at first. It flies like glass but the gimbal is another matter. It worked for the first few times and seemed to be solid on the gimbal. Maybe I keep forgetting to remove the shipping tab a few times. All it wants to do is burn itself up. It still flies even after landing upside down; RTH got carried away. But the gimbal just keeps getting worse about shaking. So I tried the whole gimbal calibration. It went to 65% before dropping out. And did it again, and it controlled the camera just fine until it failed calibration for the second time. Now when I run the camera/turn it on, all it wants to do is stick in one place, and shake around up and down to get itself into a place that jams against all motor locks. Maybe I should've left the calibration alone, but I didn't do IMU because it was flying just fine. I can't get it to stop trying to burn the gimbal up. Without power, it seems the motor just wants to lock into one location like something is forcing it to stay in that position.

Nothing useful in Assistant 2 to help me. Go 4 says I have the latest firmware. The error that kept popping up in Go 4 was I need to check the gimbal connection. Gimbal shaking error.

I got to about 51% on another attempt where the gimbal didn't move at all.

The frame and tabs haven't lipped over.

Yea gimbal ribbon cable needs replacing.

 

[lookout]

Yea gimbal ribbon cable needs replacing.

Well now I had to go and mess with IMU calibration to help the gimbal camera problem, but now I have the IMU messed up to the point that it doesn't fly any better than the cheap toys. Was it because I failed to remove the gimbal lock one too many times or something else? Factory reset probably not much of a help here.

 

[brett8883]

Was it because I failed to remove the gimbal lock one too many times or something else?

That doesn’t help but the gimbal ribbon cable is just a part that wears out after use. I think forgetting to replace the gimbal clamp after use is probably worse, however.

Even if you did everything right the ribbon cable can and will fail eventually.

Interesting to note that originally the Mavic Pro did not do a gimbal calibration on start up. This is when the gimbal swings around almost violently on start up. This was added in a later firmware update and I suspect the original spec for the gimbal ribbon cable didn’t take into account this process on every start up. Pure speculation but worth mentioning.

Just like any mechanical vehicle parts don’t last forever and it just so happens this is the weakest link in what is still a fabulously reliable machine.

 

[lookout]

That doesn’t help but the gimbal ribbon cable is just a part that wears out after use. I think forgetting to replace the gimbal clamp after use is probably worse, however.

Even if you did everything right the ribbon cable can and will fail eventually.

Interesting to note that originally the Mavic Pro did not do a gimbal calibration on start up. This is when the gimbal swings around almost violently on start up. This was added in a later firmware update and I suspect the original spec for the gimbal ribbon cable didn’t take into account this process on every start up. Pure speculation but worth mentioning.

Just like any mechanical vehicle parts don’t last forever and it just so happens this is the weakest link in what is still a fabulously reliable machine.

If I can fix the IMU back to flying I can at least find a gimbal online and just install the whole unit (just like a DJI repair shop would) or just the ribbon.

Okay watching "the video" I was able to get it flying again. So now just ordering the cable.

Do you remember which firmware that was or if it is even a firmware I can go back to?

Even when the unit is off, the camera seems to want to mechanically stay in that position when it is locking against stops?

I pulled off the ribbon on the top motor that turns it side to side, and it wants to park vertically pointing down.

 

[lookout]

Ok so I replaced the ribbon cable or so I think. I have no video feed and after reconnecting one of the ribbons I have motor movement from the gimbal. So what could I have possibly done wrong? It's still acting like it was before I replaced the ribbon. I didn't even remove the video cable from the main board.

I unplugged the motor control from the main board and somehow got the video feed back.

It still seems like to me the yaw motor is inhibited like it got damaged or burned up. Probably going to have to replace the gimbal unit.

 

[lookout]

Well I got another replacement arm gimball thing. The new motor arm seemed to work, and wasn't going berserk like the old one was. Then I try to do gimbal calibration in the DJI Go 4 app, and it tells me that the camera is already calibrated. ??? It doesn't go anywhere else after that.

But I couldn't get my old lens off at all. The videos showing that it just comes right off is a bunch of (deleted by moderator). In the meantime, putting the old camera/gimbal back on, I don't get any video feed after several attempts. So now I can't even get any video out of it.

 

[lookout]

While I had just the video cable on without the motors I noticed that the camera seemed to know which direction it was pointing as it would show up in the app. Meanwhile, I wasn't getting video. Curious if the camera gyro is what is messed up. Replug the motors back in without the video cable this time.

 

[lookout]

After messing around with the thing trying combinations of video and motor cables plugged and unplugged, at one point I had the gimbal almost fully working, but the video will probably never come back with this cable. I'm not sure how I was able to get it to work like that, but I did have the gimbal where it wouldn't look up, but it would look straight forward and straight down, but not up at all.

 

[lookout]

I got the gimbal working pretty good now, but still no video. And to get to the video cable, I have to be able to remove the lens, which isn't coming off. So I went into the app, and watched where the little gimbal ball is. I turned the drone until it was happily in the center (turned blue on the red mark). I started the camera calibration, and guess what? It started to behave. It still failed to complete, but it is mostly working at that point. I can restart it and it points forward now.

I found one broken pin on the lens side of the video cable, otherwise I would've been back in business.

 

[lookout]

I have a new gimbal and a new lens and it goes on easy. So I don't know what glue somebody put on it as it isn't coming off the old one. The way the ribbon was when I got it seems to me that it was replaced before.

I know you need to put new silicone grease on when you change a processor, but do I really need it on the camera?

Still waiting for my video cable to come...from freaking China..."US" Chinese eBay seller...if I knew it wasn't going to come domestically, I wouldn't have ordered it...UPS Surepost...sure whatever...uses BFE corporation limited which is also a Chinese warehouser...have to use 轨迹|Tracking|批量查询|电话|邮箱|PayPal交易号 to find out that it actually is coming from China...not the US....USPS only shows that it is waiting for it from shipping partner.

Looking on track24.net it won't be here for at least another month...must be held up because of Corona Virus...

Anyhow it is worth trying to solder the 20 guage video cable?

 

[lookout]

Put the bird back together with the new video cable and new gimbal assembly with the ribbon cable run the factory way (along with that). Camera calibration is successful!

This bird is beyond ready to fly again!

 

[lookout]

Now if I could just get the hang of this selfie thing....

There I am in the video window...but I don't see the selfie stick thing...where did it go? I can't see my arm extended out there...