I am new to this world so forgive me if I don't use the right words.  I just bought a used Phantom 3 Pro and a 4k.  The 4k seems to be working fine but when I try to use the Pro, I can't get the remote to link to the Copter.  I should have had him demo both but he showed me the 4k and I took his word on the Pro.  So here's what I've noticed so far:

In the app I see "Remote Controller Signal Weak" scroll across the top.  I don't see any stats from the copter and no video from the camera
On the Remote, the link led is RED and none of the controls cause any thing to happen on the copter
On the Copter:  the link led is not lit at all (I tried doing the link proceedure but pressing the button didn't do anything and the link led stayed out).  

I tried updating the firmware on the copter by placing newest firmware on an SD (formated and nothing else on it) but when I turn the copter on it attempts the firmware (gimbal led flashes red/green) for about 10 minutes, then it makes a low beep and the gimbal led turns solid red (log shows failed update).

The seller did say that a camera/gimbal cable was flaky and sometimes the gimbal woudn't track right but the camera and everything else still worked.  Would a bad cable going to the gimbal be causing all these issues?

Did you press the Re-Linking tab, in the Go app, before depressing the tiny link button on the drone?

Once you get it working, you can do a cold IMU calibration, then do the gimbal calibration.

RedHotPoker

Hi there, could you read the aircraft and controller version in About page? Please kindly offer a screenshot if applicable, thanks in advance!

RedHotPoker Posted at 2018-4-12 22:00
Did you press the Re-Linking tab, in the Go app, before depressing the tiny link button on the drone?

Once you get it working, you can do a cold IMU calibration, then do the gimbal calibration.

Yes, I did press the re-link in the app.  LED on the RC started blinking blue and beeping but pressing the tiny link button on the copter did nothing.  As I mentioned though, the Link LED on the copter is not showing any indication (no light at all).

joker04_04 Posted at 2018-4-13 04:32
Yes, I did press the re-link in the app.  LED on the RC started blinking blue and beeping but pressing the tiny link button on the copter did nothing.  As I mentioned though, the Link LED on the copter is not showing any indication (no light at all).

When I first powered it all back up this morning I did get the Link LED on the copter to blink red but the relink function still didn't work.  I powered it all down, powered it back up and tried a firmware update and that failed again and the Link LED was not blinking or present any longer.

DJI Susan Posted at 2018-4-13 01:33
Hi there, could you read the aircraft and controller version in About page? Please kindly offer a screenshot if applicable, thanks in advance!

For some reason the phone won't let me take a screen shot when inside the DJI app.  but here's what the about page showed:

App  3.1.30
Version  N/A
Remote Controller  1.9.3
Basic Fly Safe Database  01.00.01.07
Flight Controller SN  (blank)

As the copter is powered up and the RC is powered up (but not linking) I can hear a series of 3 beeps then pause then 3 beeps then pause over and over coming from the camera area of the copter

Sounds like a hardware problem.

Oh, another indicator:  When I power up the copter, the lights around it flash and I hear some beeps like a normal boot up processes but I never see the camera try to move or anything.

joker04_04 Posted at 2018-4-13 05:40
Oh, another indicator:  When I power up the copter, the lights around it flash and I hear some beeps like a normal boot up processes but I never see the camera try to move or anything.

What a drag, Now I'm getting a nauseated feeling.  The drone seems to be broken internally.
Sorry, but it may need to be assessed and repaired or exchanged.  Bummer.

Hopefully this can happen quickly, with little down air time.


RedHotPoker

I ordered a set of gimbal cables for $18...I'll try replacing all of them first and check the ribbon cable to see if it's seated or damaged.  If none of that works, it will probably be beyond my ability/desire to fix...

joker04_04 Posted at 2018-4-13 08:41
I ordered a set of gimbal cables for $18...I'll try replacing all of them first and check the ribbon cable to see if it's seated or damaged.  If none of that works, it will probably be beyond my ability/desire to fix...

Eh, I knew how frustrating this can be. I've been through it with other RC models.

Yes, try and fix it yourself, if at all possible.  I hope your attempts to repair this problem are successful, and you can continue to use the drone as it was meant to work.

I look forward to reading your happiness with this.


RedHotPoker

Got my cables and was going to replace them but found this bad spot on the OFDM module.  This is the module right under the vision positioning system.  It's also the card that has the link button on it for the RC. This damaged area is where the link button is.  If I understand it right, this could be causing the RC to not link correctly.  Not sure if this could have anything to do with the firmware not loading correctly, but one problem at a time.  Found a new OFDM (part 35) on Ebay for $40.  I'll give it a shot.

joker04_04 Posted at 2018-4-14 17:57
Got my cables and was going to replace them but found this bad spot on the OFDM module.  This is the module right under the vision positioning system.  It's also the card that has the link button on it for the RC. This damaged area is where the link button is.  If I understand it right, this could be causing the RC to not link correctly.  Not sure if this could have anything to do with the firmware not loading correctly, but one problem at a time.  Found a new OFDM (part 35) on Ebay for $40.  I'll give it a shot.

[view_image]

Thanks for keeping us updated. It is not recommended to take apart at your end which may void the warranty, please kindly note and understand. Good luck!

DJI Susan Posted at 2018-4-16 02:10
Thanks for keeping us updated. It is not recommended to take apart at your end which may void the warranty, please kindly note and understand. Good luck!

Understood...it's way outside of warranty and I prefer not to pay someone to do something I can do.  On the other hand, if I can't figure it out, then I might get the experts involved.

Thanks,

joker04_04 Posted at 2018-4-16 04:45
Understood...it's way outside of warranty and I prefer not to pay someone to do something I can do.  On the other hand, if I can't figure it out, then I might get the experts involved.

Thanks,

Well noted. Please kindly let us know if there is anything we can help.

Good to see self reliance at its finest. I hope that your experience ends with a smile.

I would not want to commit to that kind of surgery myself.  ;-)



RedHotPoker

As a follow up, I got the new circuit card in the mail and installed it.  It fixed the communication issue with the remote and I can now fly the drone! BUT, my gimbal is still dead.  It doesn't do the dance at boot up or move when commanded.  In the app I get a gimbal roll error.  I replaced all the general cables (grey and black) but haven't replaced the flat ribbon cable.  Do you guys think the ribbon cable is the issue?