there can be various other reasons due to that Samsung Galaxy S7 edge won’t turn on. As for won’t power on accompanied with 50mA-80mA boot current, the first thing we do is to check power supply voltage. If nothing goes wrong, the fault is most likely to be related to CPU. If there is abnormal voltage measured, then check corresponding faulty position on the board. The fault component is finally confirmed as PMIC U700.
The repair steps as following:
Step 1: Press the Galaxy S7 Edge power button, the phone won’t turn on. Then take out the SIM card tray and logic board.
Step 2: Confirm whether the boot current is normal, for better measurement, apply tins to the battery connector and solder a length of red supply wire.
Step 3: Trigger with tweezers to power on the phone, current reading on the ammeter is 50mA(For 50mA boot current of the phone). The fault is usually related to CPU and main power supply voltage.
Step 4: let’s measure the voltage outputted from PMIC, measure PP_0V8, PP_0V85, PP_1V8, PP_2V95, PP_1V25, PP_1V15 and PP_0V8
Step 5: Disconnect the power supply, remove the shield plate. And then trigger with tweezers to power on the phone, measure L7012, L7011, C7067, C7044, C6040, L7015 and L7004 one by one.
Step 6: Remove shield plate on PMIC with Cutting Nipper, then heat up with Hot Air Gun
Step 7: Detach PMIC from the board, apply some Paste Flux to the bonding pad. Remove tins on the pad with Soldering Iron.
Step 8: Remove tins thoroughly with rosin soaked Solder Wick, once done, clean with PCB Cleaner.
Step 9: Apply some Paste Flux to the bonding pad, get a new PMIC in position and solder with Hot Air Gun. Once done, wait for the logic board to cool for 5 minutes, at last, clean with PCB Cleaner afterwards.
Related article source: https://blog.rewatechnology.com/how-...-wont-turn-on/
The repair steps as following:
Step 1: Press the Galaxy S7 Edge power button, the phone won’t turn on. Then take out the SIM card tray and logic board.
Step 2: Confirm whether the boot current is normal, for better measurement, apply tins to the battery connector and solder a length of red supply wire.
Step 3: Trigger with tweezers to power on the phone, current reading on the ammeter is 50mA(For 50mA boot current of the phone). The fault is usually related to CPU and main power supply voltage.
Step 4: let’s measure the voltage outputted from PMIC, measure PP_0V8, PP_0V85, PP_1V8, PP_2V95, PP_1V25, PP_1V15 and PP_0V8
Step 5: Disconnect the power supply, remove the shield plate. And then trigger with tweezers to power on the phone, measure L7012, L7011, C7067, C7044, C6040, L7015 and L7004 one by one.
Step 6: Remove shield plate on PMIC with Cutting Nipper, then heat up with Hot Air Gun
Step 7: Detach PMIC from the board, apply some Paste Flux to the bonding pad. Remove tins on the pad with Soldering Iron.
Step 8: Remove tins thoroughly with rosin soaked Solder Wick, once done, clean with PCB Cleaner.
Step 9: Apply some Paste Flux to the bonding pad, get a new PMIC in position and solder with Hot Air Gun. Once done, wait for the logic board to cool for 5 minutes, at last, clean with PCB Cleaner afterwards.
Related article source: https://blog.rewatechnology.com/how-...-wont-turn-on/
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