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LG 31MU97 not powering on – How to repair this piece of sh*t

2018/04/06 7 comments

I bought the LG31MU97 in 2016 from Amazon and after 9 months, it did not power on. The reason seems to have been a power outage that somehow messed up the logic board.

So I returned it to a service center of LG to have it repaired. After 3 weeks, I received the monitor and and it worked again for 3 months.

Then after another outage the monitor was not powering on again. It was just dead. No power on sound, no LED blinking.

I contacted Amazon again, the feedback was: No we wont repair it again, the warranty is already over.

So after a while  I wanted to sell it on ebay, but they all wanted to pay below 130 EUR, which was far too less including costs for ebay and shipping.

So I decided to open this piece of sh*t.

I used some plastic cards to go between the black display cover and the silver plastic housing. There are some clamps that can be easily unhinged by using enough force.

The back cover is one piece and is somehow glued to the main part. I used a slim long metal sheet to push the adhesive away. Its around the middle and you can not break anything there.

After removing the back cover you need to unscrew the metal housing. Beware! The powersupply is then open and lead to an electric shock!

20180406_091422Next to the power connector you see some flash rom. This thing contains the logic to power on the logic board. Somehow the state of the rom is messed up. It needs a little bit of power to get it going again. This chip can also keep a state, as it is a flash rom. So if it is in the wrong state, it will stay like this. On this release of the board the logic is missing to reset the rom, if there is a sudden powerloss.

board

This is the layout from the chip.

Now comes the tricky part: IMPORTANT! YOU NEED TO POWER THE BOARD WHILE THE POWER SUPPLY IS OPEN! I STRONGLY RECOMMEND TO ASK SOMEBODY TO DO IT FOR YOU IF YOU NOT HAVE THE QUALIFICATION. I’M NOT RESPONSIBLE FOR ANY PERSONAL DAMAGE!

Cover the powersupply with a nonconducting material like a plastik mat or similar. Make sure it does not move while you work! Leave the side of the logic board open so you can work on it.

Connect the powersupply and power on the Display with the switch.

Currently it should stay in the same status, black screen and no reaction.

1

This is the layout of the power connector and the leg of the chip we need.

Now, do not directly connect anything, you will break the whole board!

2

Use an ammeter and set it to DC and V. Hold the postive to the board on postive , and the negative to the SCLK leg. Hold it some time, and pling your monitor turns on again.

I had to play a little bit checking all the legs, but only on the SCLK the monitor started to work again. I also had to repeat it until it was permanent.

Power of the monitor, let it rest for some seconds. Power it on again. If it is still dead you need to repeat it. Also check if the other legs of the ROM do have any output..

If it powers on directly again, you can assemble the screen again. It will work again.

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Categories: Uncategorized

Dell 15z 5523 not booting – not powering on – 3 beeps of death

2016/06/21 Leave a comment

I got my hands on a Dell 15z 5523 which needed a hdd replacement. After some powercycles the system wouldn’t power on properly again. It just showed a black screen which leads to a loop of 3 beeps or autopoweroff after 1 minute. After playing with pressing the reset button under the ram lid and even removing the battery I only had partly success with booting only once and then gone again. The problem is the uefi firmware which is updated or better messed up by installing Windows 10. To recover from this error you dont need to disassemble the device at all! Here are the steps:

1. Download the latest bios from dell
2. Create bootable DOS usb stick
3. Copy the xxxx.exe to the usb stick and connect to the laptop
4. Press the key “D” and hold it
5. Press the power button
6. It will come up black first so power off again
7. Repeat starting with 4.
8. The system will finally boot but might keep beeping 3 times
9. Boot from the USB stick
10. Reinstall the BIOS with xxx.exe /forceit
11. It will reboot to install the Bios again
12. After that the Laptop will boot up again properly
13. (optional) If it boots but still keeps beeping you have to disassemble it and remove all powersources and remove the bios battery. Reinstall everything and the system should be fine!

If I could help you please donate 5-10 dollars/euros to your local animal shelter! 🙂

Categories: Uncategorized

Dell XPS 15 (L502x) DVD CD-ROM drive problem

2013/01/06 2 comments

I’m running Windows 8 on my DELL XPS 15 with 256GB (3 seconds Windows boot time, any questions? :D).

So after some sleep and wake-up cycles of windows my CD drive HL-DT-ST DVD+-RW GT50N was not able to read DVDs / CDs anymore.

When a CD was installed the drive was spinning up very slowly and silent and just 2 loud movements of the optical slide and then nothing. No CD was identified at all.

Additionally, no error message was shown. Very strange.

So, i booted into my CentOS to verify the behavior. And, surprisingly, the same error occurred and the system was not able to read any disk.

I rebooted into Windows again, and as the behavior was still the same, powered of the laptop. Removed the battery and power connection. Waited for like 5 seconds, and bazinga.. the drive was working again, like nothing happened before.

As i never had these problems before, i think it might be some kind of energy-saving by Windows 8, which disables the drive and doesn’t wake up the drive completely, leaving it in an unusable state.

Internet Explorer, self signed certificates, shortcuts / pinned sites and the missing “Continue to website”-link phenomenon

2012/04/17 1 comment

Wow, Microsoft did a great job with introducing a new shortcut feature for websites with the extension .website

This will bring a lot of enhancements if you are a browser masochist and like to have pain accessing Intranet pages with self signed certificates.

So the default problem of websites with self signed certificates (admin consoles, switches, storage devices.. you name it) is the annoying popup, warning you to not access the site but rather close your browser.

Now, as used-to-microsoft-polemic-messages-admin you just go ahead and install the certificate in the trusted cert store, add the URL in the “Intranet” zone and drag-and-drop a link to you desktop and BAM.. the link is not working as you thought.

What happened? The “Continue to website (Not recommended)” link is missing. So how should you be able to access your trusted internal website with a self-signed cert if there is no option to continue?

Have a look into the shortcut you created to your site. Funny thing that link is saved as “.website”. As you might know, until now all internet shortcuts had the “.url” extension. Microsoft changed that and introduced the more secure and featuref**ing extension “.website”

Microsoft had and still has a lot of security problems which forces them to implement strange security “features”, like blocking every active content on not explicit allowed URLs (Windows 2003/2008 Strong Security enabled), blocking downloads you requested to force you to click again,… or rendering shortcuts to websites with “spoofed” insecure, certificates unusable.

If you create a shortcut to a website now, IE creates the file and sets some policy settings in it. If a website uses a self signed certificate, the browser checks the shortcut, and sets something like “Block Access, Self signed”. You can check that by changing contents of the shortcut (with notepad++ or similar) and save it. The next time you open it, Internet Explorer disables it again and writes it back to the file when the browser is closed.

Solution:

Delete all the website shortcuts created with Internet Explorer and create your own ones:

  1. Right-click on your Desktop and select “New- Shortcut”
  2. Enter the target URL e.g. http://www.google.de
  3. Enter the name for the link
  4. Click OK to finish the wizard.

This creates a file with a .url extension, which opens like charm.

You can also create new shortcuts with notepad.

  1. Create a new text file
  2. Put the following content in it:
  3. [{000214A0-0000-0000-C000-000000000046}]
    Prop3=19,11
    [InternetShortcut]
    URL=http://YOURURL
    IDList=
  4. Save it as <filename>.URL

That’s it. Your links are working again. Just prevent using the .website format.

Sony’s Kevin Butler twitters the battleship masterkey..

2011/02/10 Leave a comment

..too funny that the media agency didn’t know what that key means…

It’s time for a cup of fresh HMAC battleship coffee: