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Tag: vico won’t turn on

  • Use the Vivo T1 In the Rain and Won’t Turn On

    Use the Vivo T1 In the Rain and Won’t Turn On

    The client uses the Vivo T1 in the rain and won’t turn on after that. Let’s see the detailed troubleshooting and fixing process.

    use vivo t1 rain won turn

    Model: Vivo T1

    Announced: 2021, October 20

    Defect Phenomenon

    The phone looks very new from the cosmetics, it can be seen that the owner should cherish the mobile phone very much. But the screen turned black and cannot be turned on after using it in the rain, so it should be the boot or the display circuit with the problem. 

    We should disassemble the phone and check the parts and accessories to know the exactly defective reason.

    use vivo t1 rain won turn the cosmetic looks good

    Disassemble the Phone

    First, let’s disassemble the phone to have a check.

    Place the phone on the heating pad, set the heating temperature at around 90℃, and heat for 3 minutes. After that, the glue between the rear housing cover and the middle frame will get soft, then we can separate it easily with the plastic pry opening tool.

    use vivo t1 rain won turn separate the rear cover from middle frame

    Secondly, let’s remove the screws.

    use vivo t1 rain won turn remove the protective screws

    In the 3rd step, let’s separate the middle frame

    use vivo t1 rain won turn sperate the middle frame

    After taking off the baffle, we can see there do have some water-damaged traces.

    use vivo t1 rain won turn take off the baffle we can see there do have

    And the corresponding location on the motherboard is the battery connector. 

    use vivo t1 rain won turn corrpsonding location is the battery connector

    The waterproof mark sticker on the motherboard is also turned red.

    use vivo t1 rain won turn water proof sticker

    Then, let’s protect the cameras with tape stickers. And take out the motherboard to check carefully, after checking, there are some corrosive defects around the two shielding covers

    use vivo t1 rain won turn there are some corrosive on the shielding

    Troubleshooting & Repair

    After separating the phone, we found the most obvious defects located on the two shielding covers of the motherboard. Let’s remove the shielding covers to deal with the components and chips inside.

    Place the motherboard on the PCB holder

    use vivo t1 rain won turn place it on the pcb holder

    Heat the 1st shielding cover with the hot air gun and take it off with tweezers when the tin is melted

    use vivo t1 rain won turn heat the 1st shileding cover with hot air gun

    It does have a lot of electrolytes in it, we can clean them with the PCB cleaner first.

    use vivo t1 rain won turn clean the it does have lot of electrolytes in

    After that, apply a proper amount of solder paste flux, and heat with the hot air gun to reflow the components

    use vivo t1 rain won turn reflow the components with hot air gun

    After processing is complete, solder back the shield.

    use vivo t1 rain won turn solder back the shield

    For another shielding cover, we can deal with it with the same process

    use vivo t1 rain won turn deal with another shielding cover

    When all the components under the two shielding covers have been reflowed, let’s assemble the phone to have a test.

    use vivo t1 rain won turn assemble the phone to have test

    Plugging the USB charging cable, we can see the charging symbol, but there is no charging current

    use vivo t1 rain won turn charging symbol
    use vivo t1 rain won turn but there is no charging current

    So we should also check the charging-related parts!

    Take out the motherboard again and check the the battery connector with multimeter. After checking, one connector pin is open line, the diode value is OL!

    use vivo t1 rain won turn one pin is ol

    Check under the microscope, some of the battery connector pins are corrosive.

    use vivo t1 rain won turn battery pins are corrosived

    Let’s fix the pins by scratching off the surface corrosion first, then apply a little bit of solder paste to fix the open line rail.

    use vivo t1 rain won turn fix the ol rails

    Measure the diode values on the battery connector again, the OL is gone!

    use vivo t1 rain won turn diode value back to normal

    The battery flex connector should also be ‘refreshed’ too. We can apply a little bit of solder paste and scratch with the soldering iron slightly to make the pins shine as new.

    use vivo t1 rain won turn batteryflex connector

    Assemble and Test

    Clean the motherboard and assemble the phone to test again.

    This time, the phone can turn on normally and the charging function is OK. As we can see there’s a 1.6A charging current when connecting with the charging cable.

    use vivo t1 rain won turn the charging function back to normal

    Test the other functions are also OK.

    In the last step, assemble the rear cover with special glue, then the phone issue is perfectly repaired.

    Vivo T1 In the Rain and Won't Turn On