[Q] i9300 hardware repair help, please - Galaxy S III Q&A, Help & Troubleshooting

I've just been given two non functional i9300's for free, to see if i can repair them.
both have cracked screens, one appears to have water damage.
i've tested with spare batteries, and neither powers on, nor do they show up in windows when connected by USB.
whats the bare minimum we need for these to power on and be detected by windows, so i can determine if the logic boards in these even work?

---

Mussels84 said:
I've just been given two non functional i9300's for free, to see if i can repair them.
both have cracked screens, one appears to have water damage.
i've tested with spare batteries, and neither powers on, nor do they show up in windows when connected by USB.
whats the bare minimum we need for these to power on and be detected by windows, so i can determine if the logic boards in these even work?
Click to expand...
Click to collapse
Cracked screen and water damage will not cause the phone to not boot up. Unless the water damage is severe, it will still boot up. It appears to me tat it is either sds or motherboard.
Sent from my GT-I9300 using xda app-developers app

---

JellyYogurt said:
Cracked screen and water damage will not cause the phone to not boot up. Unless the water damage is severe, it will still boot up. It appears to me tat it is either sds or motherboard.
Sent from my GT-I9300 using xda app-developers app
Click to expand...
Click to collapse
the previous owner has disassembled them, and they had no batteries. using one from an i9305 has had no luck so far, basically just looking for advice and suggestions as where i should proceed.
if it was a PC i'd be done in seconds but fixing a phone i didnt pull apart in the first place is challenging.

---

Mussels84 said:
the previous owner has disassembled them, and they had no batteries. using one from an i9305 has had no luck so far, basically just looking for advice and suggestions as where i should proceed.
if it was a PC i'd be done in seconds but fixing a phone i didnt pull apart in the first place is challenging.
Click to expand...
Click to collapse
If we do not know why the phone is not booting up, we cannot tell u which part to change.
Sent from my GT-I9300 using xda app-developers app

---

JellyYogurt said:
If we do not know why the phone is not booting up, we cannot tell u which part to change.
Sent from my GT-I9300 using xda app-developers app
Click to expand...
Click to collapse
yeah thats the same situation i'm in.
at the very least, one of the boards is showing 5W of power consumption when connected to a wall charger (which is connected to a power meter).
since the battery is charging, that implies something is working - but i'm getting nothing on the screen and not hearing sounds out of the speaker.

---

Mussels84 said:
yeah thats the same situation i'm in.
at the very least, one of the boards is showing 5W of power consumption when connected to a wall charger (which is connected to a power meter).
since the battery is charging, that implies something is working - but i'm getting nothing on the screen and not hearing sounds out of the speaker.
Click to expand...
Click to collapse
Is tat the water dmged one or?
Sent from my GT-I9300 using xda app-developers app

---

JellyYogurt said:
Is tat the water dmged one or?
Sent from my GT-I9300 using xda app-developers app
Click to expand...
Click to collapse
i cant tell which board came from which shell unfortunately, however this board/battery is charging in the water damaged shell, but showing 0W in the 'clean' shell.
backwards to what i'd expect. maybe this ones just a dead screen, and the other has some more serious, but better hidden damage.
edit: the 'water damaged' shell + board had a red charging LED show up, that went away when i hit the power button. didnt power on after that/the touchscreen buttons dont light up when touched.
edit 2: with my good battery the LED went blue and the backlit buttons lit up. i think this hardware combo works, and i just need a new LCD - will trst it out with MHL and see if that works...

---

{
"lightbox_close": "Close",
"lightbox_next": "Next",
"lightbox_previous": "Previous",
"lightbox_error": "The requested content cannot be loaded. Please try again later.",
"lightbox_start_slideshow": "Start slideshow",
"lightbox_stop_slideshow": "Stop slideshow",
"lightbox_full_screen": "Full screen",
"lightbox_thumbnails": "Thumbnails",
"lightbox_download": "Download",
"lightbox_share": "Share",
"lightbox_zoom": "Zoom",
"lightbox_new_window": "New window",
"lightbox_toggle_sidebar": "Toggle sidebar"
}
looks like this combo just needs a digitiser + LCD, despite getting an image on screen i cant control it in any way.
thanks for the help jelly, you at least helped me think this one through and come up with viable testing methods.

---

Mussels84 said:
looks like this combo just needs a digitiser + LCD, despite getting an image on screen i cant control it in any way.
thanks for the help jelly, you at least helped me think this one through and come up with viable testing methods.
Click to expand...
Click to collapse
Welcome
Sent from my GT-I9300 using xda app-developers app

---

so using that test above (wall meter then MHL) i've confirmed that one board works, one doesnt. in either frame one board lights up the LED and the other doesnt draw any power or give any sign of life (assuming this is the water damaged one)
i've got one of everything (front + back camera module, speaker etc) literally all im missing is a LCD screen.
to ebay i go, this has been a good day

---

this just got hilariously fun.
i ended up temporarily using the LCD + digitiser from my i9305 (it works but hte back panel cant be closed) to sync up a bluetooth mouse to the phone.
now i can use it as a bluetooth controlled HTPC