Drawing ~.38A and no signs of life

If you brought a non-working phone from eBay you will have to assume it will not be an easy repair as the seller probably has had some one already look at it and since it is a new model makes it even harder. I would at least try another battery but I don’t think that will be the problem as your amp reading would point me to a short on the logic board or part connected to the board.

You could start by disconnecting all the flex cables except for the battery, charge port and see if your PC will recognise it. You will probably need to put it in recovery or DFU mode for it to be recognised. If that doesn’t work.

·         You will need to completely rule out parts by installing the logic board into a known good housing with a charged battery.

·         If it still will not boot you will need to start checking power rails.

The first line to check would be VDD_MAIN followed by the NAND power rails, this will be tricky if you are not an experienced repairer as there are no schematics for the 12 Max pro yet.

You will at least need the following equipment.

·         Multimeter with needle probes.

·         DCPS with squid leads.

·         Microscope.

·         Hot air station

·         Soldering station.

·         Heating and re-balling fixture as this board is soldered together in two halves and will most likely have to be separated and re-balled.