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Tag: huawei mate

  • HUAWEI Mate X2 Seawater Damage Repair (II)

    HUAWEI Mate X2 Seawater Damage Repair (II)

    HUAWEI Mate X2 Seawater Damage Repair (Part II)

    Let’s continue with the previous repair process. The cannot start issue has been resolved by cleaning the PCB board with the ultrasonic cleaner and jumping wires to fix the burned PCB layers.

    But the phone still with two issues

    1. The font displayed on the main screen is fatter than the normal display
    2. The outside vice screen displays the HUAWEI logo only

    Let’s fix them!

    Troubleshooting

    For the display font larger and wider, based on the repair experience it should be caused by the compass IC being damaged. Take out the motherboard and check carefully under the microscope again

    The motherboard is a two-layer combined structure and seems with some poor soldering.

    Let’s remove the upper layer of the motherboard and resold it.

    huawei mate x2 seawater damage repair ii resolder the upper layer

    Then recombine the two layers of the motherboard

    huawei mate x2 seawater damage repair ii recombine the two layers of

    After the motherboard cooling down, assemble the phone temporarily to test again. The phone still with the same issue (font is wider and bigger than normal)

    Check the motherboard under the microscope, and find there are some parts that are corrosion carbonization

    Let’s scratch them off one by one with the sculpture knife slightly

    huawei mate x2 seawater damage repair ii lets scratch them off one by

    huawei mate x2 seawater damage repair ii lets scratch them off one by 2

    Later we will deal with these pads, to resolder them.

    Then let’s find the compass chip, just as guessed, it’s corrosive so seriously and there’s almost nothing left on the motherboard.

    huawei mate x2 seawater damage repair ii the compass chip is gone  

    Let’s heat with the hot air gun and remove the residuals with tweezers slightly.

    huawei mate x2 seawater damage repair ii remove the residuals

    Then take another good compass IC from the same model motherboard, and then solder it to the motherboard.

    huawei mate x2 seawater damage repair ii take the same one

    For the signal parts, there’s a shielding cover that also gets corrosive.

    Let’s remove it and check the chips/components under the shielding cover are also seriously corrosive.

    huawei mate x2 seawater damage repair ii chips under the shielding cover

    Let’s clean the pads on the PCB with solder paste and soldering iron first. Then swap the same components and chips from the donation board.

    Assemble and test

    After soldering back the compass IC and the missing chips, let’s assemble the phone to test again.

    The phone can boot normally, and the main screen also displays normally.

    Mate X2 Seawater Damage Repair

    When folding the screen, the outside vice screen also displays normally.

    huawei mate x2 seawater damage repair ii the outside screen also

    Test the other functions one by one, everything is OK.

    The issue gets resolved perfectly by replacing a new compass IC and swapping the corrosive signal chips.

  • HUAWEI Mate X2 Seawater Damage Repair (I)

    HUAWEI Mate X2 Seawater Damage Repair (I)

    HUAWEI Mate X2 Seawater Damage Repair

    huawei mate x2 seawater damage repair png

    Model: HUAWEI Mate X2

    Announced: 2021, February 22

    Defect Phenomenon

    The phone was seawater damaged and then cannot be booted.

    The seawater is very corrosive, after the seawater damage if the phone has not been dealt with timely and properly will cause a lot of issues.

    Troubleshooting Process

    Let’s place the phone on the heating pad to heat and then separate.

    huawei mate x2 seawater damage repair put the phone on heating pad to

    After heating a while, the glue on the frame became very soft and we can separate the rear cover with a very thin plastic card easily.

    huawei mate x2 seawater damage repair separate with thin card

    Check the inside situation, the mainboard is covered with solidified sea salt.

    huawei mate x2 seawater damage repair full of salt

    Let’s protect the cameras with stickers first.

    huawei mate x2 seawater damage repair protect with stickers

    Take out the motherboard, it’s amazing that there are still so many sea salt particles inside the phone.

    huawei mate x2 seawater damage repair sea salt can be found in the phone

    Then let’s check the motherboard under the microscope carefully, as guessed, there are many components on the motherboard that are corroded.

    huawei mate x2 seawater damage repair the corrosive parts on motherboard

    After checking, many capacitors and resistors are missing. Besides this, even a small shielding cover has fallen off, and many areas with green/blue corrosive electrolytes.

    Like this kind of serious corrosion, we have to remove all the shielding covers and clean the components inside with the ultrasonic cleaner + PCB cleaner liquid thoroughly.

    huawei mate x2 seawater damage repair remove the shielding covers

    huawei mate x2 seawater damage repair ultrasonic cleaner to clean the

    After cleaning, scratch off the corrosive and blacken pads carefully.

    huawei mate x2 seawater damage repair scratch off the corrosive and

    The 1st stage of physical cleaning is finished, let’s clean the motherboard with the PCB cleaner + brush again.

    Then connect with the DC power supply machine to have a test, after testing, there is a large current leakage.

    huawei mate x2 seawater damage repair large current leakage can be

    huawei mate x2 seawater damage repair large current leakage

    Where there is current leakage, there is a hot component or chip. Let’s inspect the motherboard under the thermal imager, and find the heat is coming from the PCB layers.

    huawei mate x2 seawater damage repair find the heat is come from pcb

    We can see the corrosive from the side of the PCB board.

    huawei mate x2 seawater damage repair the inner rail is broken

    For this kind of defect, we can only fix it by scratching off the layers and jumping wires to fix it.

    huawei mate x2 seawater damage repair scratch off the layers

    There are many layers inside the PCB board, so we need to scratch off layer by layer until reaching the layer that has no short.

    huawei mate x2 seawater damage repair scratch off many layers already

    The scratching-off layers process requires a lot of patience and carefulness.

    Then the next step, we need to jump wires.

    How to Jump Wire

    First, apply some UV mask and cure it with a UV lamp for isolation

    huawei mate x2 seawater damage repair apply uv for isolation

    Secondly, there’s no inner layers structure for this model on the bitmaps yet. So we should scratch off the layers on the same motherboard for reference to avoid wrong jump wire connections.

    huawei mate x2 seawater damage repair the same motherboard for reference

    In the third step, let’s refer to the good motherboard to jump wires

    huawei mate x2 seawater damage repair jump wires layer by

    After jumping wires, apply some UV mask for isolation and strengthen again.

    Mate X2 Seawater Damage

    Assemble and Test

    When the motherboard cooling down and the UV mask is isolated, let’s assemble the phone to have a test.

    huawei mate x2 seawater damage repair assemble the phone to test

    The phone can start up

    huawei mate x2 seawater damage repair can start up

    But there are still some other issues when entering into the system

    1. the display is abnormal on the main screen, the font display wider and fatter than normal
    2. the outside vice screen displays the HUAWEI logo only, and cannot enter into the standby user interface

    huawei mate x2 seawater damage repair fatter and wider display

    huawei mate x2 seawater damage repair the outter screen abnormal display

    For the two issues, let’s continue to introduce the repair method in the next article.