RC USB Failure - Preliminary Failure Analysis and Fix

Joined
Mar 28, 2016
Messages
2
Reaction score
4
Age
76
Many people have had RC USB port “failures” and I am (was) one of them. Having had a lot of experience in developing and manufacturing electronics, I decided to look for the root cause of these failures before I sent my RC back to DJI on the RMA they provided and wait 1-3 weeks for the RC to be returned. At this point, I no longer have to send many RC back as I found the problem and easily fixed it.

It is interesting that in talking to two different DJI reps, neither had heard of RC USB failures as a widespread problem! In searching for my own solution, I came across a large number of posts with people having the same issue but the only resolution was to either send the RC back for repair or upgrade to the HDMI module.

So… basically the root cause of the problem seems to be a design error where the wrong USB connector was specified or manufacturing substituted/used the wrong type of USB connector. The small USB interface board is designed and constructed with all SMT (Surface Mount Technology) components. SMT components are typically soldered to the board using a small amount of solder paste stenciled onto each connection point, components placed in position, and reflowing all the solder paste joints at once in a reflow oven. The issue is the USB board has a footprint for the large USB connector that is for a TH (Through Hole) part yet is was soldered to the board as an SMT part. This mismatch causes a very fragile set of solder joints which eventually will become intermittent or fail completely, as in my case.

Note that the typical “tests” for a bad USB port is to see if the attached phone or tablet is charging and the DJI GO app connects to the RC. There are 4 pins on a USB connector: VUSB (+5V), Ground, Data + and Data -. If the bad connection is on VUSB and/or ground the attached device will not charge. If either of the Data lines are not connect the attached device will not connect to the app. In my case, the device was charging but there was no USB communication with the app (or memory stick, etc. for upgrading firmware).

I repaired my USB board is less than 5 minutes simply by manually reflowing the solder joints on the connector.

I am not totally sure of the type of USB connector on the board and would like to investigate this problem further. To do this I would have to remove the USB connector and inspect it. I do not want to do that for fear of voiding my warranty. If there is anyone who had this problem and “fixed” it by upgrading to a HDMI module, I would be interested in evaluating the old board. If you have such a board and are willing to part with it, please start a private conversation with me so we can make arrangements to get me the board.

Once I am sure of my analysis, I’ll put together a little report and instructions for fixing modules if anyone wishes to do so.

Thanks

Al
 
Great post. Thanks.

It's hard to imagine that the DJI reps had never heard of the RC USB failures. Either they are not being truthful or they are really just clueless. Both are very sad.
 
  • Like
Reactions: JoBe
Neither of the two rc I have used have charged the device connected android and iOS.


Sent from my iPhone using PhantomPilots mobile app
 
I thought IOS did not charge and Droid does.
Just going by what I have read in here.
 
  • Like
Reactions: Ainsley
Many people have had RC USB port “failures” and I am (was) one of them. Having had a lot of experience in developing and manufacturing electronics, I decided to look for the root cause of these failures before I sent my RC back to DJI on the RMA they provided and wait 1-3 weeks for the RC to be returned. At this point, I no longer have to send many RC back as I found the problem and easily fixed it.

It is interesting that in talking to two different DJI reps, neither had heard of RC USB failures as a widespread problem! In searching for my own solution, I came across a large number of posts with people having the same issue but the only resolution was to either send the RC back for repair or upgrade to the HDMI module.

So… basically the root cause of the problem seems to be a design error where the wrong USB connector was specified or manufacturing substituted/used the wrong type of USB connector. The small USB interface board is designed and constructed with all SMT (Surface Mount Technology) components. SMT components are typically soldered to the board using a small amount of solder paste stenciled onto each connection point, components placed in position, and reflowing all the solder paste joints at once in a reflow oven. The issue is the USB board has a footprint for the large USB connector that is for a TH (Through Hole) part yet is was soldered to the board as an SMT part. This mismatch causes a very fragile set of solder joints which eventually will become intermittent or fail completely, as in my case.

Note that the typical “tests” for a bad USB port is to see if the attached phone or tablet is charging and the DJI GO app connects to the RC. There are 4 pins on a USB connector: VUSB (+5V), Ground, Data + and Data -. If the bad connection is on VUSB and/or ground the attached device will not charge. If either of the Data lines are not connect the attached device will not connect to the app. In my case, the device was charging but there was no USB communication with the app (or memory stick, etc. for upgrading firmware).

I repaired my USB board is less than 5 minutes simply by manually reflowing the solder joints on the connector.

I am not totally sure of the type of USB connector on the board and would like to investigate this problem further. To do this I would have to remove the USB connector and inspect it. I do not want to do that for fear of voiding my warranty. If there is anyone who had this problem and “fixed” it by upgrading to a HDMI module, I would be interested in evaluating the old board. If you have such a board and are willing to part with it, please start a private conversation with me so we can make arrangements to get me the board.

Once I am sure of my analysis, I’ll put together a little report and instructions for fixing modules if anyone wishes to do so.

Thanks

Al
I have long electronics design and assembly experience. I will analyze my board and will give you a feedback.
 
  • Like
Reactions: Ainsley
Would be nice to have the iOS pads charged by the RC.
 
  • Like
Reactions: JoBe
Many people have had RC USB port “failures” and I am (was) one of them. Having had a lot of experience in developing and manufacturing electronics, I decided to look for the root cause of these failures before I sent my RC back to DJI on the RMA they provided and wait 1-3 weeks for the RC to be returned. At this point, I no longer have to send many RC back as I found the problem and easily fixed it.
Not to necro an older thread, but with the P3's no longer in production, putting more info out there on this can only help others IMO.

I have symptoms of this, where the communication between my android device and the transmitter (gl300b) stops working, and the android just shows a grey video still and says 'disconnected', but I can still control the bird (P3 Pro).

I found this thread suggesting that it's the USB port, so I took mine apart and looked and sure enough, it looks a lot like they used a SMT port on a through-hole section of the board. The port on my board says 150825 on the top, but nothing turns up when I google for it.

Myself, I'm going to check my parts pile and see if I can find a through-hole port and look at replacing the stock one.

I can pull the photos from my phone and post them if they would help
 
Not to necro an older thread, but with the P3's no longer in production, putting more info out there on this can only help others IMO.

I have symptoms of this, where the communication between my android device and the transmitter (gl300b) stops working, and the android just shows a grey video still and says 'disconnected', but I can still control the bird (P3 Pro).

I found this thread suggesting that it's the USB port, so I took mine apart and looked and sure enough, it looks a lot like they used a SMT port on a through-hole section of the board. The port on my board says 150825 on the top, but nothing turns up when I google for it.

Myself, I'm going to check my parts pile and see if I can find a through-hole port and look at replacing the stock one.

I can pull the photos from my phone and post them if they would help

I remember this post when it first appeared. I am having the same issue but I have already at the original posting of this thread installed the HDMI module. So, it is not only happening with the original non-HDMI module, but also with the HDMI module installed. It seems this post has fallen out of circulation. But, if someone has a fix, I would be very interested. I have had so many problems with this, I have probably blamed firmware for it and I have also changed the USB cables hoping it would work (which seemed to help infrequently). I would hope you can find a fix and let me know or if not, to let me know as well. Thanks for your post.

[Edit] I don't however, recall having issues with the original non-HDMI module. I'm thinking of removing the HDMI module and trying the original module to see if it also happens.
 
Last edited:
I remember this post when it first appeared. I am having the same issue but I have already at the original posting of this thread installed the HDMI module. So, it is not only happening with the original non-HDMI module, but also with the HDMI module installed.
Hmm, good to know, as that was one of my options, replacing the original board with a HDMI model.

I may have to take mine out and do an experiment...

My thoughts are that if the board is indeed a through-hole design for the port, that adding some short wires to go through the holes and soldering them to the leads that are on the port itself should work, but as one can see from the pictures, there isn't a lot to work with without risking melting the plastic innards. Finding a port with longer leads to begin with would be the better option, but finding one that will fit in that spot on the board may be a bit of an issue

usb_port_p3p_closeup.jpg usb_port_p3p_under.jpg
 
Many people have had RC USB port “failures” and I am (was) one of them. Having had a lot of experience in developing and manufacturing electronics, I decided to look for the root cause of these failures before I sent my RC back to DJI on the RMA they provided and wait 1-3 weeks for the RC to be returned. At this point, I no longer have to send many RC back as I found the problem and easily fixed it.

It is interesting that in talking to two different DJI reps, neither had heard of RC USB failures as a widespread problem! In searching for my own solution, I came across a large number of posts with people having the same issue but the only resolution was to either send the RC back for repair or upgrade to the HDMI module.

So… basically the root cause of the problem seems to be a design error where the wrong USB connector was specified or manufacturing substituted/used the wrong type of USB connector. The small USB interface board is designed and constructed with all SMT (Surface Mount Technology) components. SMT components are typically soldered to the board using a small amount of solder paste stenciled onto each connection point, components placed in position, and reflowing all the solder paste joints at once in a reflow oven. The issue is the USB board has a footprint for the large USB connector that is for a TH (Through Hole) part yet is was soldered to the board as an SMT part. This mismatch causes a very fragile set of solder joints which eventually will become intermittent or fail completely, as in my case.

Note that the typical “tests” for a bad USB port is to see if the attached phone or tablet is charging and the DJI GO app connects to the RC. There are 4 pins on a USB connector: VUSB (+5V), Ground, Data + and Data -. If the bad connection is on VUSB and/or ground the attached device will not charge. If either of the Data lines are not connect the attached device will not connect to the app. In my case, the device was charging but there was no USB communication with the app (or memory stick, etc. for upgrading firmware).

I repaired my USB board is less than 5 minutes simply by manually reflowing the solder joints on the connector.

I am not totally sure of the type of USB connector on the board and would like to investigate this problem further. To do this I would have to remove the USB connector and inspect it. I do not want to do that for fear of voiding my warranty. If there is anyone who had this problem and “fixed” it by upgrading to a HDMI module, I would be interested in evaluating the old board. If you have such a board and are willing to part with it, please start a private conversation with me so we can make arrangements to get me the board.

Once I am sure of my analysis, I’ll put together a little report and instructions for fixing modules if anyone wishes to do so.

Thanks

Al
Did you find out if this was the problem? As I seem to be having the same problem....everything worked fine, then didn't. RC simply won't connect to app...doing my head in now!!
 
I have the same issue, has anyone had any success with this? did you just heat up the solder and reflow it?
 
I have the same issue, has anyone had any success with this? did you just heat up the solder and reflow it?
That's how it is done. Just don't pull the traces off of the circuit board. You will need some solder wick if you are going to pull it off and replace it.
Look at the solder points under a magnifying glass to see if the solder points have been pulled up. If so, you will need to repair it.
 
I have a kind of the same issue.
Phantom 3 pro RC link fine to the AC (control gimbal, take pictures, motor start, and fly fine) but tablet is in charge mode all the time
Is the USB defective or only the solding? I tried to reflow but still no success.
Thanks all.
 
Last edited:
Anyone has a tip or a hard reset pin on how to reset the controller?
I did reflow the USB (put a little more sold, I use a contact cleaner product all over the usb point. tried 10 different cable and they all do is only charging the tablet.
The GL300B just work fine with the drone itself , I can fly my P3P drone OK, I can shoot video, take picture, fly left right up down
without the tablet connected.
but no info..
I called DJI support and no help at all.
Thanks
 
Interesting article. I have just thrown away a cable as it wasn't connecting my Android to the controller. A replacement cable worked but just maybe there is a loose joint in there! As a retired (Navy) electronics engineer, maybe need to check the soldering on the board!
 
Just for information. SUCCESS
out of the blue my tablet just partially reconnected. I have now a no signal in RED instead of a grey not connected
I pressed and hold all the button possible with the controller ON >> C1, C2, record to the left, shutter to the right, ISO wheel, playback total of 6 button pressed and hold then I power off the controller keep pressing all of then and power on RC and a miracle happened >> RC connected to tablet
maybe it's luck.
The status light when I re powered the RC went from a solid blue to no blue at all then I released all the button.
I updated to the newest DJI go app 3.1.50 for Android
and now all is reconnected I have full status
expect live view from the gimbal because a a faulty overheated processor winch I will be reprogram soon (another self help support)
 
Last edited:

Members online

No members online now.

Forum statistics

Threads
143,066
Messages
1,467,354
Members
104,934
Latest member
jody.paugh@fullerandsons.