Lenovo "lavie z" laptop- overvoltage on usb hub fried motherboard help

Lenovo (made by NEC) “lavie z” (aka model hz550) laptop, accidentally plugged in the wrong power cord (12v dc instead of 5v) to a powered external usb hub that was plugged in to a onboard usb port for 1 second, got a little burning smell, and laptop shut off. I still see charging led when plugged in, and another led comes on for a second when I push the power button, but no other signs of life.

I have enough experience with small/component level circuit board repair, reflowing, and similar to not cause additional damage & have a proper workstation/ micro soldering setup and tools etc , but most of my experience is on (older) cell phones.

I have examined the motherboard carefully under 10x and I didn’t find any visibly damaged or burnt areas. I’ve cleaned with 99% alcohol and an ultrasonic cleaner & reassembled. I’ve attached a photo of motherboard.

If anyone can point me in the right direction on where to look (on the motherboard for what might be damaged), solutions that might involve physically disabling the onboard usb hub/controller, etc, OR any resources that might help identify components on this motherboard, I’d VERY greatly appreciate it. Thanks in advance!

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note: apologies about selecting the wrong model , ifixit doesn’t have this model “hz550” aka “lavie z” or hz750 (similar, lavie z 360 touchscreen) as an option

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Can you carefully peel off the sticker (13D11/150/001etc) and check if there is a 'board number" printed on the board beneath?

It would be useful to find the schematics and sometimes they can be found online but searching online using what I can see on the board gives no results. Only result was for the BIOS files when searching for "Lavie HZ550"

Just a thought.


Thank you, the part number for the motherboard wasn't to be found printed anywhere, I already had the stickers off previously and searched all the edges and obvious spots, but google helps a little- Lenovo part # for mb seems to be:


The "type" or sub model of the hz550 seems to be "20fg"

This was built by nec for Lenovo and also sold by NEC as the "lavie z"(model) , but I don't think they sold many outside of Japan. Another part # from one of the stickers on the back is "607-13D11-150" REV "Z3T" but not much on google for that one

Again- any input or resources would be very greatly appreciated!


Hi @Greg

It’s not so much the part number that you want, rather it is the “board number”. This is the number used by the board manufacturer to denote the board and that will get the schematics. The part number is what is used by the laptop manufacturer (in this case Lenovo) for whom the board was made to identify the board for their own uses, i.e. what board goes in what model when assembled or for replacement purposes if board fails.

When you search for the part number (select by part number, not by Machine type) that you posted (5RPWW00017) here you get 1 result which shows:

W10P,BRW UCi7,INT,WOTP system boards

When using that info you get these results, none for schematics though


Here’s some more info for a LaVie Z HZ550FG taken from this webpage Have tried searching using the info seen on the stickers in the disassembly guide, to no avail

Maybe contacting this schematics supplier will get you somewhere further, just a thought.