ipad a1893 6th generation charging problem

Hello everyone,

One of my customers brought me an ipad 6th gen A1893. When i plugged the ipad to usb charger with a screen on it, it shows me ipad starts charging with 5.1V and 2.6Amp just for 2 seconds then goes off and loops the same thing always.
As you all know there is only pdf schematics and no boardview for these devices on internet I couldnt manage to find the problem.
is there anyone who can show me a way to find out the problem

Thank you.