|UPair One - Main Board with ESC controllers|
As you can see, there are 6 mosfets driving each motor in each quadrant. I'm not sure what the four chips are towards the center of the board, but I believe that they are the controller IC's for each motor. The red/black leads on the top and bottom of the board are 5vdc power for the navigation LED's.
The GPS controller board is where I believe my problem with the "NO MAV DATA" is originating but until I hear back from Banggood, I'm not sure.
UPDATE: After several weeks and a hundred more flights, the motors again wouldn't arm. Not seeing anything physical on the boards, I let the quad sit on the shelf for a couple of months while focusing on my Phantom 3 Pro, but out of curiosity and an electronics background, I decided to try the heat gun fix to the GPS board. I heated the large IC in the center of the board to about 400° and also the SD card mount (that was super glued by Bangood). Lo and Behold, it worked!. There is either a flakey IC, solder connection or SD card involved here that the heat restores the connection. It's still working so far! (December 2017)
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