SAMSUNG S10 Plus Not Charging Issue Repair

S10 Plus Not Charging Issue Repair

Model: SAMSUNG Galaxy S10+

Announced: 2019, February 20 

Defect Phenomenon

The customer was drunk, and the next day when woke up found the phone not charging and cannot be booted.

It might be caused by water damage…

Troubleshooting

Place the phone on the heating pad to heat for a while, when the glue between the back cover and middle frame starts to melt, insert a prying piece to separate.

Then check the details inside, there are no obvious water damage signs.

Then connect the motherboard with the DC power supply machine to test, and find a 50mA current leakage.

And there’s no response when pressing the power button. Then take out the motherboard and check the cosmetic carefully, after checking, no abnormalities can be found.

Remove the heat dissipation sticker on the motherboard with the hot air gun.

Then connect with the DC power supply and check under the thermal image camera again. As we can see, there is a chip that gets extremely hot.

After that, replace the little PMIC chip with a new one

1. heat the chip with the hot air gun
2. then take it up gently when the tin gets melted.
3. Clean the PCB pads with the hot air gun, PCB cleaner, and solder wick
4. Solder back a new chip with the same specification (do not reverse the chip direction)

Then let’s assemble the phone and test it with the DC power supply machine again, but find there still has a 50mA current leakage. The issue is not fixed yet!

Then let’s remove the shielding covers on the motherboard and carefully check again.

Check under the thermal image camera again. Still, it’s the little PMIC chip gets hot

This little chip is integrated with the charging IC function, so we wonder if it’s the second stage of the power supply with the problem. 

(Here, for the 2nd stage power supply you can refer to SAMSUNG S10 course content)

Let’s measure the seconds stage (VBAT) diode value

It’s normal!

But when we jump over the IF PMIC to power the motherboard directly, there is a short again. Which is really strange.

Anyway, let’s jump a wire first

 then apply the DC power and check under the thermal camera again, find it’s this little chip get hot.

The thermal imager can locate a rough range, so we’ll use the rosin inspection method to double confirm the shorted component.

Apply rosin on the surface of the chips and components, then connect with the DC power supply and apply voltage again. Now we can see the shorted component easily.

It’s this little capacitor that gets shorted, remove it with a tweezer slightly.

After that, assemble the phone and test it, the phone can boot normally, and the charging function, as well as other functions, are all OK.