iPhone 5 touch issue - GSM-Forum

short_toground · 12-10-2016, 02:04

Original screen was cracked and replaced. Touch issue became intermittent.

If phone battery drained and recharged touch would work fine. Until it stopped responding to touch completely.

lean226 · 12-10-2016, 05:24

It sound like touch ics issue. Reflow or better reballing sage and cumulus ics.

Enviado desde mi iPhone utilizando Tapatalk

short_toground · 12-10-2016, 15:40

Is that a common problem with the 5? Never heard of touch ic issues before 6 Plus

lean226 · 12-10-2016, 17:15

Ups! Sorry, it is iPhone 5, i thought it was 5s. Maybe the display PMU is not working properly.

Enviado desde mi iPhone utilizando Tapatalk

short_toground · 12-15-2016, 23:31

So I checked schematics and I have 5.7v at Sage but PP5V1_Grape_VDDH is missing at Cumulus

Should that always be present when screen on? There's PP1V8_Cumulus_vddldo that's missing too. Is that ONLY generated when PP5V1_Grape_VDDH present?

No shorts on either of those lines

short_toground · 12-16-2016, 13:11

Anyone? Please help need data

short_toground · 12-16-2016, 23:17

Does anyone know if cumulus gets power when a signal is passed through the screen or if it just gets power when device woken up from Stand by?

I tried injecting 5.1v into cumulus and pp1v8_grape but still no touch function.

Can someone help explain to me. Thanks!

ctccellulaire · 12-17-2016, 12:27

Quote:

Originally Posted by short_toground

Does anyone know if cumulus gets power when a signal is passed through the screen or if it just gets power when device woken up from Stand by?

I tried injecting 5.1v into cumulus and pp1v8_grape but still no touch function.

Can someone help explain to me. Thanks!

your problem is easy

as we know voltages in electronic devices is contained (VOLTAGE+DATA"function") so it's not a battery to supply it with 3.8 DCv so it will charge !!!
to sum up you must understand what is happening you are at a good Level of understanding and maintain phones maybe other devices, anyway bro
your problem is (touch work for sometime then hang)
also you mentioned that you have
PP5V1_Grape_VDDH
PP1V8_Cumulus_vddldo
Missing!

it's not a 100% condition to have a short in a cap or other component to judge if damage or not you have to inspect each piece alone so to make it easy for you do the following:
1-connect LCD and test your missing voltages if they are still missing then you have problem in TOUCH circuit what does that mean ? well, when we say TOUCH problem we mean by this to check every tiny component and IC that is related to touch !!!
so no one can give you 100% clear-cut where might the problem would be we can't guess ! so scientifically you have to test when LCD is connected and for instance it must be 100% original even if broken ! then test your missing voltages
so
your complete solution would be like:

1-PP5V1_Grape_VDDH (LCD TOUCH power supply voltage)
it is generated by AGATHA chip (Power ic)
U7 pin(P13) PASSING by C324,C369 to U12 (CUMULUS) pin(C8)
2-PP1V8_Cumulus_vddldo Also it's generated by U7 AGATHA PP1V8_GRAPE PASSING by XW36 to be as (PP1V8_CUMULUS_VDDLDO) then C372 to supply TOUCH IC

PP1V8_GRAPE aslo passes R2(Pull-up resistor) Ending in U5

this is what you must check one by one ! depending on what you said ! I don't know if connector is good or lcd is good or it's software problem or even maybe Proximity problem !

Kind regards

ADONIS IRAQI

short_toground · 12-17-2016, 14:14

Thanks for responding.

I've checked all that but still missing the voltages.

I'm trying to understand if those voltages should be there regardless if screen is good or not.

Are they enabled through the digitizer or always present? Another thing I need to know is sequence. Is one voltage generated first before others?

Also what does XW36 mean?

ctccellulaire · 12-17-2016, 15:49

professional info can't share everything for free !

I apologize

short_toground · 12-17-2016, 15:55

Quote:

Originally Posted by ctccellulaire

professional info can't share everything for free !

I apologize

Cool glad to know it's all about money

ctccellulaire · 12-17-2016, 16:15

Quote:

Originally Posted by short_toground

Cool glad to know it's all about money

NOPE, no one would share for free ! because these info are hidden that's why there is LEVELS in maintenance and hardware repair !

not only money maybe other things to get in return did anyone shared with you ?
the info I shared ?

Regards

short_toground · 12-17-2016, 16:18

Quote:

Originally Posted by ctccellulaire

NOPE, no one would share for free ! because these info are hidden that's why there is LEVELS in maintenance and hardware repair !

not only money maybe other things to get in return did anyone shared with you ?

the info I shared ?

Regards

I already knew the info you shared I need to know sequence of voltages so can further trace the issue

usernome · 05-16-2018, 20:30

Did you solve the problem ?

12-10-2016, 02:04	#1 (permalink)
short_toground No Life Poster Join Date: Jul 2016 Posts: 536 Member: 2598526 Status: Offline Thanks Meter: 52	iPhone 5 touch issue Original screen was cracked and replaced. Touch issue became intermittent. If phone battery drained and recharged touch would work fine. Until it stopped responding to touch completely.

12-15-2016, 23:31	#5 (permalink)
short_toground No Life Poster Join Date: Jul 2016 Posts: 536 Member: 2598526 Status: Offline Thanks Meter: 52	iPhone 5 touch issue So I checked schematics and I have 5.7v at Sage but PP5V1_Grape_VDDH is missing at Cumulus Should that always be present when screen on? There's PP1V8_Cumulus_vddldo that's missing too. Is that ONLY generated when PP5V1_Grape_VDDH present? No shorts on either of those lines

12-17-2016, 14:14	#9 (permalink)
short_toground No Life Poster Join Date: Jul 2016 Posts: 536 Member: 2598526 Status: Offline Thanks Meter: 52	iPhone 5 touch issue Thanks for responding. I've checked all that but still missing the voltages. I'm trying to understand if those voltages should be there regardless if screen is good or not. Are they enabled through the digitizer or always present? Another thing I need to know is sequence. Is one voltage generated first before others? Also what does XW36 mean?

12-10-2016, 05:24	#2 (permalink)
lean226 Junior Member Join Date: Dec 2016 Posts: 20 Member: 2657403 Status: Offline Thanks Meter: 20	It sound like touch ics issue. Reflow or better reballing sage and cumulus ics. Enviado desde mi iPhone utilizando Tapatalk

12-10-2016, 15:40	#3 (permalink)
short_toground No Life Poster Join Date: Jul 2016 Posts: 536 Member: 2598526 Status: Offline Thanks Meter: 52	Is that a common problem with the 5? Never heard of touch ic issues before 6 Plus

12-10-2016, 17:15	#4 (permalink)
lean226 Junior Member Join Date: Dec 2016 Posts: 20 Member: 2657403 Status: Offline Thanks Meter: 20	Ups! Sorry, it is iPhone 5, i thought it was 5s. Maybe the display PMU is not working properly. Enviado desde mi iPhone utilizando Tapatalk

12-16-2016, 13:11	#6 (permalink)
short_toground No Life Poster Join Date: Jul 2016 Posts: 536 Member: 2598526 Status: Offline Thanks Meter: 52	Anyone? Please help need data

12-16-2016, 23:17	#7 (permalink)
short_toground No Life Poster Join Date: Jul 2016 Posts: 536 Member: 2598526 Status: Offline Thanks Meter: 52	Does anyone know if cumulus gets power when a signal is passed through the screen or if it just gets power when device woken up from Stand by? I tried injecting 5.1v into cumulus and pp1v8_grape but still no touch function. Can someone help explain to me. Thanks!

12-17-2016, 15:49	#10 (permalink)
ctccellulaire Freak Poster Join Date: Dec 2014 Location: PCB Posts: 315 Member: 2320407 Status: Offline Thanks Meter: 88	professional info can't share everything for free ! I apologize

05-16-2018, 20:30	#14 (permalink)
usernome No Life Poster Join Date: Jan 2003 Location: Iassy Age: 59 Posts: 4,314 Member: 19723 Status: Offline Thanks Meter: 359	Did you solve the problem ?