SAMSUNG Galaxy S10 Boot Problem Reparatur

SAMSUNG Galaxy S10 Boot Issue Repair Cases sharing.

Case 1.  SAMSUNG Galaxy S10 Cannot Boot

The phone can still work the night before, but the next day it just stopped working suddenly.

Reparatur-Prozess

• When receiving the phone, connect with the adapter to charge there’s no charging current. Then disassemble the phone and connect it with the DC power supply to check, there is a 52mA current leakage. 

• Then measure the diode value on the main power supply, the diode value is 64 only. 

• After carefully checking, found it’s U2001 get damaged. Remove it first, then measure the diode value of the main power supply, it’s back to normal. There is no current leakage anymore.

• Replace the U2001 with a new one, then the issue gets fixed.

Case 2.  SAMSUNG Galaxy S10 Keep Rebooting After Water Damage

Client feedback: this phone dropped into water then keep restarting.

Reparaturprozess: 

• First, for the water-damaged phones, there might be some components or chips that get corrosive by an electrolyte. So we can disassemble the phone, take out the motherboard to check the cosmetics first.

• After checking we find the cover under the flashlight with a little bit of corrosion sign. The remove the cover to check the chips and components under the shielding cover.

• Is that possible the issue is caused by the pads being corrosive under the chip and components?  As we can see from the above picture, after cleaning there is no obvious corrosive damage. But still let’s resolder the chip to have a try.

Then connect with the DC power supply again, there is still a 32mA current leakage

• Like the small current leakage normally is caused by chip damage, then we can apply with DC power and feel the heat components with finger or lips (not recommended, haha)

The below area gets hot!

• And on the backside is the charging IC, the parts number is MAX77705C.

• This chip is just like the charging IC, it will switch the main power into the secondary power supply, we check the secondary power supplies, it’s also with 32mA current leakage.

• So there is a high chance the issue is caused by this chip. Remove it and test, there is no current leakage.

• Then replace it with a new one. After that, assemble the phone to test, all functions are OK. The issue gets resolved by replacing the charging IC.

You can visit REWA Academy to learn the detailed SAMSUNG S10 Theory and Troubleshooting Course