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Laptop repair.

April 5th, 2017, 8:34


Sorry no HDD question but a laptop PCB question.
yesterday my 6 year old son spilled some lemonade on my laptop.
After cleaning everything it still worked. But a few hours later it stopped working.
I opened it up and spotted some lemonade on my mainboard.
After cleaning the whol board with alcohol and putting it back together everything was ok except the audio to my speakers.
Windows says that there are no speakers connected or headphones. I tried everything rolling back drivers, installing new ones and uninstalling.
Even made a Ubuntu Usb stick, which also does't recognize audio equipment.
Bluetooth audio works with a bluetooth heradphone.

The other thing the HDMI output finds my TV but it not seding any video signal.

After i looked back at my pictures i saw that the one chip that had lemonade on it was located next to my HDMI port, so i'm guessing that's the part which is failing. It is a RT9025 25ZSP LDO. Could this part cause my problems and could it cause the rest functioning properly???
I attached a picture of the lemonade spill and IC.
Hope someone can help me test the IC and telling me some more info.
Laptop specs:
Lenovo 700-15isk
8 gb ram
256gb ssd
gtx 950m

Kind regards,

Re: Laptop repair.

April 5th, 2017, 10:10

Why would you expect a forum on hard drive technology/data recovery be a source of help on a motherboard component repair problem? You are more likely to get help at the BGA Reballing Club forum, HF Harware forum, or TechSupport forum.

Re: Laptop repair.

April 5th, 2017, 11:43

i had previously a good experience with some of you guys about a hard drive. So i thought maybe i could post it over here. The level of experience with electronics is very high with you guys (reverse egineering, experience with electronics and so on).
Didn't actually know of the existance of the other forums, so thank you for the links. Will ask over there.
Kind regards.

Re: Laptop repair.

April 5th, 2017, 12:25

It possible that the issue may be because of the residue.
Is it too painful to disassemble and clean? Either way, another thorough clean would at least give peace of mind.

Re: Laptop repair.

April 5th, 2017, 12:53

I already cleaned it twice now. Sprayed almost half a spray can of alcohol (ipa). And brushed with a toothbrush. Still not working. Maybe the component has gotten defective.

Re: Laptop repair.

April 5th, 2017, 13:02

Liquid spills are notoriously difficult to repair. You think you have it fixed yet it keeps failing later. If you don't do component lever motherboard repairs, about all you can do is give it a thorough clean (in an ultrasonic cleaner, preferably) and hope for the best. You would need the schematic diagram for the motherboard and have to have a lot of experience troubleshooting motherboards to hope for much success. You can view some YouTube videos that might help, but it's a daunting job.

Re: Laptop repair.

April 5th, 2017, 13:26

Hello ,
Its been a while since i have repaired any laptops now ,In a laptop there will be a sound chip and sometimes a amplifier chip increasing output of sound chip .Please trace and see if you have one chip or both of these ,These once are the likely culprits please try and replace them first

Re: Laptop repair.

April 5th, 2017, 19:08

There are several good component level technicians at the badcaps.net forum. Don't be put off by the site name -- not everyone is a "recapper".

BTW, here are several IdeaPad circuit diagrams:

Re: Laptop repair.

April 5th, 2017, 19:27

Measure the voltages at all 8 pins.

Datasheet (RT9025-25ZS):
http://www.richtek.com/assets/product_f ... 025-05.pdf

The part number suffix denotes a 2.5V LDO regulator.
RT9025_pinout.gif (8.5 KiB) Viewed 7007 times
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