iPhone 13 Pro Maxmobile phone repair without charging

iPhone 13 Pro Maxmobile phone repair without charging

“Machine model” iPhone 13 Pro Max

[Fault phenomenon] The customer described that he put his mobile phone on the bedside before going to bed at night, and as a result, he got up the next morning with no electricity at all. He thought that the charger was broken, but when he used the charger to charge other mobile phones, he found that the charger was normal, cleaned the charging interface, and changed a charger to charge this mobile phone, but it could not be charged.

Usually, this situation may be caused by battery failure, battery discharge and motherboard problems. The daily problems of battery or motherboard are slow charging and fast power consumption, or the charging port is damaged or loose, which makes it impossible to charge normally.

IPhone 13 Pro Max mobile phone maintenance without charging Figure 1

[Maintenance process] After receiving the customer’s mobile phone, disassemble the mobile phone, remove the motherboard, and charge the battery separately. It is normal. When charging the mobile phone with a special charging tool and data cable, it is found that 5V is pulled down and there is a short circuit, which is generally caused by the damage of the charging chip or capacitor on the motherboard circuit.

Because the iPhone 13 Pro Max adopts a double-layer motherboard design, it is necessary to layer the motherboard when locating the fault point.

IPhone 13 Pro Max mobile phone maintenance without charging Figure 2

After layering, the lower board was tested to be normal, and the charging voltage of 5V was pulled down when testing the upper board. Check Xinzhizhao.Point bitmapIt is found that there are only capacitors on the 5V charging line of the upper plate, which may be the problem of short circuit of the capacitors of the upper plate. After all the capacitors on the line are removed, the situation that 5V is not pulled down is tested, and several capacitors are removed from the same position of the feeding plate to make up the parts.

IPhone 13 Pro Max mobile phone maintenance without charging Figure 3

[Maintenance result] After the capacitor was replaced, the single upper layer test was carried out. After the test, the charging was normal, and the bonding test was also normal. After the reinstallation test, the mobile phone was turned on normally, the network was normal, the charging was normal, and the fault was perfectly repaired. The maintenance ended here.