Advanced Gps unconnected

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Hello i bought used p3 advanced online and they guy said it flys but there is something wrong with the camera transmission and the gps. When i got it the camera worked perfectly but the unit would not take off and said "gps unconnected".

So i went online and read some forums and i thought ill risk getting a new gps receiver. so i crossed my fingers and went on ebay and bought a "known good" gps recover my the drone.

When it came i put it into the phantom 3 advanced and it was still saying "gps unconnected" Bugger

The main board still looks good. Do u guys think i am missing something or you have something more i could try doing?
 
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Inspect the board, especially solder joints around the FC. The solder is most likely broken there.

Also check connector with a multimeter. If it has power, you can also check what's visible on communication lines.
 
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20211001_205646.jpg


There are the solder joints and I can't find anything wrong with them maybe I am just not looking right

When I use my multi meter and when there is no gps connected I get 3.3v on all pins
20211001_205529.jpg
 
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I'm wondering y i would have voltage by the rx if there is nothing connected but maybe the pin is pulled up. If there would just be a way to bypass the gps i would be perfectly fine with that. maybe ground the int pin? or what does the int pin do on the gps? or can i do something in the software yet?
 
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Dji Flight Controller will not let you start the drone without GPS initialized.
I did looked at motor start conditions in the firmware a few years back, but can't remember much now.
There were various conditions involved in the motor start decision.

Options:

There is like a thousand of FC parameters which you can change by connecting the drone to PC via front USB. You may browse through these, maybe something will look like gps ignore option.

Or if you're good enough at software, you may extract the FC firmware from update, open in a disassembler and apply symbols which O-Gs published - this is how I looked at the code. Then you will easily find the function which decides on motor start.
 
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I'll see if I can tackle the first option. Set the fc parameters. One question what software do I use to change those parameters? Link?
 
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The photos you posted are the main board, I think, not the GPS unit which is mounted in the top shell. However, the top photo does show the GPS connector and as you changed the GPS unit it for a "known good" one it might be all right.
Have you checked the cable from the GPS unit to the main board, are the pins all connected to the wires? Do a continuity check between the GPS board and the plug???
53e22a594e42e78b4a067bfa1ca4004a.jpg
 
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Yup I changed the gps unit and it's still the same. I just did a continuity test and all seemed fine. It would be a blast getting the gps to work. Would there be a place to send my main board to and they would do a component level repair. Or would I be best off just to get a "known good" board? It would be nice if I could fix it though. It wouldn't be something else like another board on the drone? Here are some more pics, see if u can see something...
20211002_194956.jpg
20211002_194945.jpg
20211002_194951.jpg
 
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Where are you hoodan? Certainly sounds like a main board issue getting the same problem with two GPS units.
Plenty of new and good boards available here in the UK.
You could "clean" the main board a bit, bit of WD40 on a soft cloth and dab it over the board, might cure something.
 

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