iPhone 4 Proximity sensor not working logic board problem ! & iphone
Hi, hopefully someone will be able to to be helped me here. I purchased a used iphone 4 online and in the description it stated it had a new screen fitted but the proximity sensor didnt work. I assumed it would be a very simple fix and set about trying to fix it today but after 3 hours and literally trying everything i could try it still doesnt work.
What ive tried so far:
1. Several new screens including original apple screen from another phone.
2. Colored in the small window above the spaeaker grill Along with black marker (common fix)
3. Placed black electrical tape over the window (another common fix)
4. Several new proximity flex cables (all tested and confirmed working on another phone)
5. Factory reset the iphone
What Ive discovered:
Looking at the logic board under a microscope i found a missing component directly above the power button flex connector. Checking the schematic i found on here its a capacitor (i presume) labelled C4_PMU. I replaced this component Along with another one from a spare iphone 4 logic board but still the proximity sensor doesnt work
Does anyone know if this capacitor has anything to do Along with the prox sensor or has anyone got any other suggestions i can try.