acer iconia tab a1 830 not charging or power on

[Doc38343]

Hey just tinkering and revisiting some abandoned devices using my new microscope and this tablet - acer iconia tab a1 830 was abandoned here a couple of years ago. We thought the Micro USB charging port was broken but the guy had told me he replaced it. I took the microscope and looked at it and the solder job was horrible it has a pin under the bottom SMD jack that should have been done with hot air. It looked like he had done it with an Iron by just holding it to the jack casing. SO I removed it cleaned and tested the jack off the board and it was fine so i soldered it back. Now I still get nothing past a little device marked KGJB4M but I can find no info on it.
Would anyone happen to have a schematic or service manual for one of these?
(I am mostly practicing and trying to learn more on board level issues)
None of the components have the mask markings to identify their location.
found a lot of user manuals but nothing else.
If I knew what that IC was and pin out it would help.
Thanks

I will get some better pics using my USB scope in a few got busy for a sec...

[Doc38343]

Re: acer iconia tab a1 830 not charging or power on

Hey i know this thing isn't worth anything but the idea is to learn by tracing the board fail and if i destroy it there is no great loss... I really need a schematic though. I cannot identify the IC that the 5v stops at and don't know if there is another rail of 1.5 or 3.3 missing that would turn the IC on.

I figure practice on this as opposed to a $800 board....
need the experience.
Thanks!

[Sojke]

Re: acer iconia tab a1 830 not charging or power on

Did you manage to fix it? I have one that wont charge the battery.