NEEDED IPAD7 A2197 DIODE MESURAMENTS VCC_MAIN, VCC_BATT, VDD_BOOST

[jolivares]

I sent IPAD 7 WIFI-2019, model A2197 to a techincal service, but they did not repair it, so i am trying to fix it. The problem is the IPAD is not booting and no turn on.
This is what i found until this moment:
1) with battery connected, the current draw from the power supply is about 450mA from the charging port.
2) no short circuit in lines VCC_MAIN, VCC_BATT.
3) with the power supply, or with the battery, the 3.7V of VCC_MAIN and 1V8_ALWAYS are generated without problem.
4) the current draw from the power supply, without battery, is about 26mA from the charging port.
5) i haven't the diode mesurements of the main lines if power, so i dont known if i have a fuge in VCC_main or other line of principal power.
THE VCC_MAIN DIODE THAT I MEASURED: 0.178V
6) i dont know what other test or action i have to do to diagnostic the fault.

I'll appreciate so much your help.
God bless you, and thanks for this forum.

Post data: sorry for my english, is not very well.

[mon2]

1) with battery connected, the current draw from the power supply is about 450mA from the charging port.

Do you see this current draw immediately or does the current draw slowly climb to this value?

Watch this video:

iPad pro 10.5 Won't power on. What is it this time. (youtube.com)

[jolivares]

Thanks for the response.
the current draw is immediately.
the other issue is the current draw from the battery connector, is about 0.8mA, rising slowly to 1mA, and then falling slowly until the original 0.8mA.
i will watch the video now.

[mon2]

If the current draw is immediate then most likely there is a shorted part on the board. Consider to use the schematic with no battery power to the board -> meter in resistance mode -> measure the resistance to ground of each and every inductor on the board. No power to the board during these tests. We are checking for a shorted / low resistance on a power rail. Alex has at least this video on ipads with shorted / defective parts.

[mon2]

Must read this thread..

https://www.badcaps.net/forum/troubl...a2197-no-power

[jolivares]

Very thanks! the post that you share was very usefull, i am reading and checking if i have something similar i my case.
God bless you.