Use screwdrivers and other phone opening tools to disassemble the iPhone XS Max, remove the iPhone XS Max display screen and iPhone battery, and then take out the iPhone XS Max motherboard.
Use SS-T12A pre-heating station to separate the iPhone XS Max motherboard, and then put it on the iSocket test fixture.
Now we need to remove the glue for iPhone CPU, put iPhone motherboard under a microscope, and then use BGA graver blade to remove the glue around the CPU.
Apply some solder paste around the CPU, and then use hot air gun and BGA graver blade to remove the iPhone CPU. After the iPhone CPU is removed, use soldering iron to handle the residual glue on the solder pad, and then use JBC soldering station to solder a jump wire from 17 Pin to test if the circuit between iPhone CPU and iPhone infrared camera 17 Pin are disconnected.
Reballing the iPhone CPU, and then install the iPhone CPU back to the motherboard. After the motherboard is cooled, use digital multimeter to measure the 17 Pin, now the resistance value is back to normal.
Next, use iSocket test jig to test it, the iPhone XS Max Face ID tested is normal. Assemble the iPhone XS Max layers, and then install the iPhone XS Max, turn it on, all function tested are normal.