Lenovo Ideapad 320 No Power Successfully Revived

I successfuly repaired this Lenovo Ideapad 320 laptop with board id NM-B242 Rev 1.0. According to customer, they used universal charger and set to 24V causing the laptop not to power on because of overvoltage.

I check for shortage using power supply but it has zero ampere. I dismantled the unit and check if there was a burnt components, but the board was clean and shinny.

I check 19V rail. I measure voltage input of the first mosfet, it has 19V. But on the output side, it has zero volt. I thought the culprit was the 2nd mosfet. But before I checked the 2nd mosfet, i disconnected the jumper PJ301. Then measured the output of the second mosfet if it has 19V. YES, it has! Therefore the problem lies on 19V rail.

So, I downloaded the schematics, and check the 19V rail. By analysing the schematic diagram under page 53, I planned to lift PQ314 hoping that this mosfet was leaking. I lifted the mosfet, then checked 19V at current resistor PR301. Huwaw!!! 19V was there! I quickly replaced PQ301 N-Channel type mosfet. Now the laptop has been revived.

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Lenovo Ideapad 320

board id NM-B242 Rev 1.0

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ACER E5-411 No Power [FIXED]

Laptop ACER E5-41 comes with no power. I checked if shorted to ground on battery terminal and charging terminal, and it was really shorted. Full shorted. I first download its schematic and analyze the circuit. I removed PQ24 and check if the board was still shorted to ground. Stiil yes. Until I realize that the charging ic OZ8691LN is shorted. I removed it. The short was gone. I replace the charging ic with a good ic, but symptoms persist. Im sure that charging ic that i put in was good, so I decided to look for another defective parts. I found out that PU5, the 3.3valw ic was heating up. When i remove it, the short was gun. Finally I replace the ic and the laptop works perfect.

DOWNLOAD Acer e5-411=1=Quanta ZQM_UMA

acer e5-411 schematic diagram

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iPhone 5s Schematic Diagram

Here is an iPhone 5s schematic diagram(iPhone 5S 820-3292-A) downloaded from other sites, and reuploaded b me on my mediafire account. The schematic diagram is in PDF file so Adobe Reader must be installed on our laptop.

DOWNLOAD iPhone 5s Schematic Diagram

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OPPO R831K Shorted Solution

This is an OPPO R831K water damage unit. I checked it and the board was shorted. It has many corroded parts. Just remove the capacitor C1838 that is connected in Vbat_PMU with respect to ground as shown on the image below.

remove C1838

After removing the capacitor, the shorted was gone and the unit can now power on.

DOWNLOAD OPPO R831K Schematic Diagram

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iPhone 5 Schematic Diagram

DOWNLOAD iPhone 5 Schematic Diagram

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iPhone 6 Plus Schematic Diagram

DOWNLOAD iPhone 6 Plus Schematic Diagram

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