3GS white Screen, another SOLUTION! – iphone mobile problem
3GS White-Screen another solution:
Check the LCD-Boost-Voltage Circuit! You MUST connect the LCD to check this Voltage!
PS: Dont look exactly on this Board, i took it from my Spare-Parts Box
this points must short ,on my board was damaged
I have the same problem and I mesure 4,6 volts at this point. What is wrong now?
Thanx in advance…
Where can you see, that there has to be a connection between these two points?
Check the Resistance to GND at this point whitout Battery connected and post Result. Maybe the Capacitor has a little short and pull down the voltage. I had this also 1 time.
Thanx in advance…
Thanx for reply. I mesure 100 KOhm. Is there a way to troubleshoot some values?
Can you give external 5.5V there for testing? Remember, you must disconnect the battery before you try again. Once booted Along without success, you want to reset the board!
iphone 3gs lcd ways solution
Check the LCD-Boost-Voltage Circuit! You MUST connect the LCD to check this Voltage!
PS: Dont look exactly on this Board, i took it from my Spare-Parts Box
hi ive a iphone 3gs Along with Along withe screen it turn on but i cant look only Along withe touch screen it not work but the phone is on and work if i call the phone it work ! if i connect to itunes ( itunes work and look phone )
ive cheked this another test poing and when i start the screen the voltage it is 0v what i can do ? where is the problem ?
thanks for support
Your LCD is good? If not, you have also 0V there.
Do you have a short on this line? If not, check for +VBATT at L12_AP first.
Look at the schematics, this is a simple circuit!
BR Matthias
lcd is good ive try to nother iphone3gs and work good

short where ? ive look +vbatt on L12_AP is in this pic ? lokk th pic and ive mesurated 3,8 volt
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pls want hel for this it is right 3,8 v in this point ? if ive not 5,5v in the capacitator where i can found this voltage in the board where start this voltage
thanks i wait
The Voltage starts there! Check also at C242_RF
Look at the schematics! Its so simple…
ok simple but im a beginner yung technics
and i want to be directed to the right way 😛
now look this pic ive cheked

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in this case i want replace u20_AP right ?