| Hello,
After cleaning up an old water damaged iphone 5 the touch screen stopped working after a week where everything on the phone worked.
I have checked all connections on the connector and they are fine.
I have checked the two supply voltages for U14 they are also fine 5,7V and 1,8V.
When checking U12 (touch controller) the supply voltage measured on C372 should be 1.8V (PP1V8_GRAPE) but is always 0V. The 5.1V (PP5V1_GRAPE_VDDH) supply to U12 measured on C369 is 0.038V.
I have tried to heat up the U12 with 320 C for 25 sec, no change.
I guess there is a short somewhere, but cant find it / mesasure it. I measured 280 ohm over the C372 capacitor on a working iphone, but on the broken one there was infinite ohm, so maybe it is a lose connection to the U7 power chip?
What do you think? |