IPhone 6 no touch even after replacing both touch IC's
 

hi guys

i have an iphone 6 touch issue, no water damage but maybe dropped not sure
what done so far

replacing U2401, U2402,U1501, checking voltages all present only one voltage is missing PP5V1_GRAPE_VDDH also there is no short or low reading on this line and i checked from under U1501 to under U2401 and it's connected, any idea please?

thanks

check all capastors between the touch ics...you will find solution

Do you think the 5V for PP5v1_GRAPE_VDDH is missing because of those IC's? Anyway will check tomorrow morning hope i find a faulty cap there

if you tried all and nothing reball CPU A8 Chip 100% done
Regards

Sent from my SM-G935F using Tapatalk

Should i ise diod mode to check them?

just checked and found these voltages PP1V8_GRAPE and PP_CUMULUS_VDDCORE and PP_CUMULUS_VDDANA are missing i checked the lines no short or low readings so i reball and replaced the Power ic but still no PP1V8_GRAPE.

any Ideas???

hello did you repeal and replace your PMIC or juste reball and replace ??
(to make that touch work again ;-p)

for the PP1V8_GRAPE it can be the U2403 shorted or bad or your cumulus shorted or bad

check also your CUMULUS_TO_PROX_TX_EN_BUFF on Q1101 and R2407 near the U2403

U2403 and U2401 been replaced still no touch

i have 3 iphone 6 the same problem no touch screen
i changed u1501 and both ic touch
but not solution
pp 5v1 grape is 0v

Check

CUMULUS_TO_SAGE_BOOST_CLK_EN
TOUCH_TO_SAGE_VCM_IN_CONN