6 
22 iPhone 6s No Image (no water damage) Display completely Black
Hi Guys..
I m here again for expert advises and for learn reparing :)
My client sent me iphone 6s wth no image.
The phone is second hand, so they dont tell me anything about phone history.
I check with new display but the screen remain black, itunes recognize phone.
I search on web and found this video
https://www.youtube.com/watch?v=dYbW35dl...
Try to putout C4200.
fortunately the first component (c4200) is shortage and i solve the problem.
Obviously you are thinking, if everything is ok, why i m here, :)))
I m here because i want to learn and understand how find the problem on the phone and not just solve the problem searching in net or putting out every component.
My question is :
In this case, which is the first step.
Before searching on the web i check if the backlight is present,
i check all backlight filter, check FPC connector if damage.
MY proper question is this line DISPLAY POWER PP5V7_LCM_AVDDH must have 5 volt???
so i check a phone who run perfectly (without lcd / touch panel)
If there is no problem in the phone, i find 5 volt here (c4200)?
Which is the right way to proceed in this case, if i have only schematic and not INTERNET :) Thanks a lot for attention.
Questa è una buona domanda?
40 
2 Commenti
@refectio Sir.. do you have some suggestion plz := ??
da AGS
@refectio what do you think? It's my understanding that PP5V7_LCM_AVDDH does have (needs) 5.7V and C4200 should show 5V. Would you start with Chestnut and work toward the end of the circuit at the connector? Of course I may be way off with my schematic :-)
da oldturkey03