User friendly repair 😅. Zeus 3, 9" doesnt boot up. Emmc replacement and reprogramming. Bga 153 package. Bga 153 means that chip has 153 pins and here is the picture for comparison with 1 cent.
This process is extremly hard, a lot of things can go wrong and it takes around 3,4 hours. Board needs to be preheated over specific time on around 150 C for flux to activate. After that higher temperature needs to be applied for desoldering and soldering back old chip. When the chip sits back in place board needs to cool down in steps. Fast heating or fast cooling can cause microfractures of vias, layers and traces on multilevel boards. When you are looking at youtube soldering of bga chips most of them don't mention those kind of things and they are doing it all wrong which can cause irrepairable damage. Also cleaning old solder balls directly with solder wick and soldering iron like we see on youtube is not smart on this board, you will end up lifting pads, special technique that I developed over time needs to be applied. Not to mention that memory chips are tied with software ID, so for programming some workarounds are needed. In translation if you switch EMMC chip from one chartplotter to another it just won't work. Up and running again.
