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Expert Guide: iPhone X Not Charging Fault Repair

As we know, iPhone X is the latest iPhone models designed with many new features, obviously it's one of your best choice when choosing cell phones, but there are some faults you can't avoid whatever cell phone you use. In this article, we are going to repair an iPhone X charging fault.

First of all, be clear about the iPhone X charging principle, we can check on WUXINJI Dongle. Plug iPhone data cable, the iPhone tail plug connector J6400 47/48 pin gets 5V input voltage PP_VBUS1_E75, at the same time, the 20 pin HYDRA_CON_DETECT_CONN_L will be pull down.

5V of PP_VBUS1_E75 send to U3300, after R3360 output PP_VBUS1_E75_RVP, finally sent to U6300.

HYDRA_CON_DETECT_CONN_L is renamed HYDRA_CON_DETECT_L by R6410.

HYDRA_CON_DETECT_L send to the multifunctional electronic switch tube U6300 G3 pin, when the U6300 received a low power lever signal, then access identification iPhone lightning cable.

If U6300 received the 5V power supply, and detected after the tail plug access，it will transmit information to the CPU via UART data interface. After the iPhone charge control IC U3300 received the 5V, it will transfer the information of the external 5V to the CPU VIA R3332. In this time, the iPhone battery icon will turn to green and the lightning sign appears.

When the iPhone needs charging, the U6300 will send open signal HYDRA_TO_TIGRIS_VBUS1_VALID_L to U3300, U3300 works, and then the iPhone start to charge.

Now we've got clear about the principle, next, we are going to measure the detection signal HYDRA_CON_DETECT_L that from the interface to U6300, it is normal.

Measure the 5V voltage PP_VBUS1_E75 with Fluke 15B+ Digital Multimeter, the data only has 4.5V, the problem was found. If the U3300/U6300 can't detect the normal 5V, the iPhone X can't be charged.

Measure the diode data for 5V, it is more than 1600, which is abnormal. After replace the U3300 and then measure it again, the problem still there. Now, with the help of the QUICK 861DW hot air rework station and tweezers, we've replaced the all circuit components that are connected to the PP_VBUS1_E75_RVP that are converted by U3300, but the data tested still is abnormal.

Check the peripheral circuitry of each attached chip, when measuring the U3300 TIGRIS_LDO，it is short circuit, and this voltage only connects 2 capacitance.


Replace the capacitance, now the iPhone X can be charged, everything goes well.

More cell phone repair skills and related repair tools you have need, please contact us on www.vipfixphone.com

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