iPhone X not charging/ fake charging - GSM-Forum

fozzo · 05-24-2022, 19:35

Hello Guys,
I might need some help with this one as I running out of ideas.

Got an iPhone X dead. Customer said it was in charging and then the charger smoke and got burnt.

Upon connecting to the bench supply it was consuming 0.04a before prompt to boot but it was booting anyway. I disconnected all cables to check if any part was causing the issue but the absortion was still there. So I split the motherboard and the upper part was still getting 0.04a. After using thermal camera I found out it was tigris2 u3600 which was causing the issue since it heated more than any other part. After changing it was at 0a before prompt to boot so it looks like it was resolved. I started testing whith motherboards still split using an adapter and I discovered it was not charging. After further investigation It looks like VDD_MAIN was way too low, about 0.7v, from usb which normally leads to L3341 and L3340 so I changed them but didn't get any better result. I then changed u6300, u6200 and Q3350 but it didn't give any change.

Strange enough it charges if the battery is out of charge at 1.6a untill it starts to boot and it stops charging while is booting, furthermore it charges if I power off the device during charge. The only option I see is to change PMU u2700 but I'd like to see if any of you have any other ideas.
Thanks

fozzo · 05-25-2022, 09:43

Alright, after further checking I managed to solve.
I double checked all u3600 pads in diode mode and I found out TIGRIS_PMID1 was reading OL which is not correct. Checking schematics and following the line I discovered DZ3300 was burnt as well. After changing this diode VDD_MAIN voltage came back to 4V with only charger which let me understand the board if fully functional.
After testing the motherboard in a socket I can say it is charging correctly.
I don't know if this might help someone.

05-24-2022, 19:35	#1 (permalink)
fozzo Junior Member Join Date: Oct 2014 Posts: 33 Member: 2273262 Status: Offline Thanks Meter: 5	iPhone X not charging/ fake charging Hello Guys, I might need some help with this one as I running out of ideas. Got an iPhone X dead. Customer said it was in charging and then the charger smoke and got burnt. Upon connecting to the bench supply it was consuming 0.04a before prompt to boot but it was booting anyway. I disconnected all cables to check if any part was causing the issue but the absortion was still there. So I split the motherboard and the upper part was still getting 0.04a. After using thermal camera I found out it was tigris2 u3600 which was causing the issue since it heated more than any other part. After changing it was at 0a before prompt to boot so it looks like it was resolved. I started testing whith motherboards still split using an adapter and I discovered it was not charging. After further investigation It looks like VDD_MAIN was way too low, about 0.7v, from usb which normally leads to L3341 and L3340 so I changed them but didn't get any better result. I then changed u6300, u6200 and Q3350 but it didn't give any change. Strange enough it charges if the battery is out of charge at 1.6a untill it starts to boot and it stops charging while is booting, furthermore it charges if I power off the device during charge. The only option I see is to change PMU u2700 but I'd like to see if any of you have any other ideas. Thanks

05-25-2022, 09:43	#2 (permalink)
fozzo Junior Member Join Date: Oct 2014 Posts: 33 Member: 2273262 Status: Offline Thanks Meter: 5	Alright, after further checking I managed to solve. I double checked all u3600 pads in diode mode and I found out TIGRIS_PMID1 was reading OL which is not correct. Checking schematics and following the line I discovered DZ3300 was burnt as well. After changing this diode VDD_MAIN voltage came back to 4V with only charger which let me understand the board if fully functional. After testing the motherboard in a socket I can say it is charging correctly. I don't know if this might help someone.