P3P Crashed.. No video/limp gimbal.

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New to the forums here and hoping someone can help me out! I recently crashed my P3P into a tree which resulted in a torn gimbal ribbon cable. Upon replacing the ribbon cable, my drone would start up with a "limp" gimbal, in other words it wouldn't spin around on start up like usual, it just sits there completely lifeless. Upon firing up the DJI GO app I quickly discovered I had no video feed and it said my remote/drone/battery had outdated firmware. Tried to update the RC firmware. Now it won't even link to the drone. The drone shows flashing yellow lights (very quick at that) indicating that the drone is indeed not linked to the remote. I've tried to pair the drone manually with no luck. The remote has a solid red light upon turning it on. The drones beep code is the usual beep it always has done when starting up.
 
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Update: 7/3/2020 @ 5:08PM

Determination pays off. I was able to link the drone and remote after endless attempts of manually linking it via the button combination on the remote and pushing the button the drone itself by doing what I should have done in the first place: connecting the remote to my phone via usb and opening up the DJI GO app. I was able to link the RC via the app. Now I have a whole slew of messages popping up about errors and such. Posting a picture in a few moments..

Edit: I still have no video transmission. I have also noticed that the board where the manual link button is has been getting extremely hot after just a minute or so of being on.. is this normal or possibly a sign of malfunction?
 
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I have also noticed that the board where the manual link button is has been getting extremely hot after just a minute or so of being on
We typically use board names from here:
O-Gs wiki - Ph3 board names

Link button is on OFDM Receiver board. It normally does NOT get hot. You way want to check which chip does that.
If there's a short on the board, I suspect buck converters (VUBI chips) would be overheating.
 
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We typically use board names from here:
O-Gs wiki - Ph3 board names

Link button is on OFDM Receiver board. It normally does NOT get hot. You way want to check which chip does that.
If there's a short on the board, I suspect buck converters (VUBI chips) would be overheating.
Thank you for the link. That will make my life and everyone else's a bit easier. As far as the OFDM board, I'm assuming the heat coming from it is related to the no video feed issue in the app. Here's a screenshot of what I currently see:

Screenshot_20200703-185316_DJI GO.jpg
Screenshot_20200703-185433_DJI GO.jpg
Screenshot_20200703-185503_DJI GO.jpg
 
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I’m thinking the gimbal top board is what’s causing the issue. With or without an SD card (with the latest firmware on it) it quickly blinks green for around a minute and then it switches to a slower red and green flashing as if it’s updating. Then it stops. Then the red and green will begin again only for it to eventually go back to the flashing green.

This along with the lack of any gimbal movement and lack of video feed is leading me to believe it’s the gimbal top board causing the issues.

Is it worth it to try and open it up and see if there’s anything physically wrong or should I just attempt to replace it?
 
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Make the flying part work first, then go to gimbal.

Until you make the body fly, disconnect the gimbal completely.
If something overheats w/o camera, fix the overheating before connecting camera.
 
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Make the flying part work first, then go to gimbal.

Until you make the body fly, disconnect the gimbal completely.
If something overheats w/o camera, fix the overheating before connecting camera.
Appreciating the answers quaddamage- it's keeping me motivated. I found that both the OFDM board and the board underneath it in the VPS housing (having trouble figuring out the name of this board even with the guide- sorry) have quite a bit of heat coming from them. The OFDM being the hotter of the two as it literally burns my fingers after about two or three minutes of being on and yes the fan is on and working!

I think I found a seller of both the OFDM board and the mystery board underneath it for around $140.. looking like my best option at this point.
 
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Below OFDM there's VPS Module Board. Not entirely sure, but I think the drone will fly if you disconnect that one.
OFDM is required - it allows Lightbridge link to your RC.

If you want to diagnose the OFDM - the simplest way is to spill alcohol over it while it's working. The alcohol will immediately start evaporating, and the place which dries up first is the source of the issue.
 
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Below OFDM there's VPS Module Board. Not entirely sure, but I think the drone will fly if you disconnect that one.
OFDM is required - it allows Lightbridge link to your RC.

If you want to diagnose the OFDM - the simplest way is to spill alcohol over it while it's working. The alcohol will immediately start evaporating, and the place which dries up first is the source of the issue.
Does it have to be 99% or would the lower grade 85% work as well? I'm assuming you mean rubbing (isopropyl) alcohol? Do I need to pour a lot or a little? Should I keep it away from the cables and/or connectors?

Sorry for the million questions but I would rather ask and learn opposed to be shy and learn nothing. If someone has knowledge I do not posess I find it an absolute waste to not absorb what information I can.

I appreciate your answers quad!
 
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Does it have to be 99% or would the lower grade 85% work as well?
Above 80% should be ok in this case; always better to use cleaner one, but that board only uses low voltages, so will be ok.
You can use both IPA and ethyl alcohol; I usually use 95% IPA.
You don't have to pour much of it, just enough to make the chips wet. Then you look at which element/elements dries out immediately.

The best case it - the element which dries out will be a capacitor; caps can sometimes develop a crack and short the circuit; they're easy to replace. If what dries first is an IC, that's harder - they require more skill to replace, and often they can get hot because of other components around them - so you're never sure that's a cause and not just effect.
 
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Above 80% should be ok in this case; always better to use cleaner one, but that board only uses low voltages, so will be ok.
You can use both IPA and ethyl alcohol; I usually use 95% IPA.
You don't have to pour much of it, just enough to make the chips wet. Then you look at which element/elements dries out immediately.

The best case it - the element which dries out will be a capacitor; caps can sometimes develop a crack and short the circuit; they're easy to replace. If what dries first is an IC, that's harder - they require more skill to replace, and often they can get hot because of other components around them - so you're never sure that's a cause and not just effect.
Headed to the store to grab some iso and I'll give it a shot! I appreciate the advice and I'll let you know what I find. Thank you very much!
 

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