Backlight is flickering, possibly damaged internals?

Question

Lenovo N22 Chromebook

A chromebook produced by Lenovo in 2016 for educational use.

crwdns2934591:011crwdne2934591:0 crwdns2934593:0crwdne2934593:0 | crwdns2947278:025crwdne2947278:0 crwdns2947270:0crwdne2947270:0

Dylan Hafley @stevonnie4ever

crwdns2934065:0crwdne2934065:0: 1

1

crwdns2931729:0crwdne2931729:0: Mha 13, 2021

crwdns2933897:0crwdne2933897:0

Backlight is flickering, possibly damaged internals?

I power on my Chromebook, it seems fine at the bright white boot screen, but once I get to something dimmer (Discord window, wallpaper, anything dimmer than pure white), I notice a rapid flicker on the screen. The backlight never completely dies out, but the flickering is an eye strain and a huge annoyance. I already tried this guide in an attempt to get at the ribbon cable and nudge it back into place: Lenovo N22 Chromebook Screen Replacement

But now…I think I've done something horribly wrong. I tried to follow these steps, and made it as far as step 2. I have an N22 Touch rather than just the N22, but I figured that besides the touch screen they would be pretty much the same on the inside. But once I tried to lift up the keyboard, and felt some resistance, and found that in the top-right corner (by the power button), there appeared to be a piece of metal with a screw attached to the underside of the keyboard. When I tried to loosen this screw, it didn't budge. Possibly stripped? I can't lift the keyboard at all. Help!

crwdns2934089:0crwdne2934089:0 crwdns2934093:0crwdne2934093:0

crwdns2934109:0crwdne2934109:0

crwdns2853045:0crwdne2853045:0 crwdns2853046:0crwdne2853046:0

crwdns2889612:0crwdne2889612:0 0

crwdns2947414:01crwdne2947414:0

I have this issue too, with a new Chromebook. It was worse on my old one because I dropped the laptop, messing up the screen, so I got the laptop as a replacement. The screen issue used to be so bad my cursor was affected. I removed my extensions, powerwashed and reset ChromeOS settings AND flags to default. The screen improved but the flickering backlight with the cursor (mostly in incognito tabs or anything that isn't white) still happens.

I don't know what to do. I can't replace the screen myself because I'm not good with technology at all, but when I replaced my screen, my webcam quality got messed up and the screen was worse for wear. I just got this laptop last week. I'm so frustrated!

crwdns2934271:0Mha 2, 2022crwdnd2934271:0 Tia crwdne2934271:0

crwdns2934285:0crwdne2934285:0

crwdns2933315:02crwdne2933315:0

I have this issue too, with a new Chromebook. It was worse on my old one because I dropped the laptop, messing up the screen, so I got the laptop as a replacement. The screen issue used to be so bad my cursor was affected. I removed my extensions, powerwashed and reset ChromeOS settings AND flags to default. The screen improved but the flickering backlight with the cursor (mostly in incognito tabs or anything that isn't white) still happens.

I don't know what to do. I can't replace the screen myself because I'm not good with technology at all, but when I replaced my screen, my webcam quality got messed up and the screen was worse for wear. I just got this laptop last week. I'm so frustrated! — Tia

score 2 · Answer 1 · 2021-08-13T18:47:50-07:00

crwdns2934057:0crwdne2934057:0

jayeff @jayeff

crwdns2934065:0crwdne2934065:0: 500.4crwdns2936485:0crwdne2936485:0

11

388

1.5crwdns2936485:0crwdne2936485:0

crwdns2931729:0crwdne2931729:0: Mha 13, 2021

crwdns2933897:0crwdne2933897:0

Hi @stevonnie4ever ,

The hardware maintenance manual for the touchscreen model doesn’t mention any screw attached to the keyboard only the ones holding the upper case assembly to the base and the cables attached from the motherboard to the keyboard and the touchpad. (see p.25)

On p.31 is shows how to remove the LCD module and on p.33 how to disassemble the module so that you can check if the video cable connection to the LCD panel is secure.

If the panel is faulty the part number for a touch LCD panel is 5D10K85106. Search online using the part number only to find suppliers that suit you best.

Have you proved that the problem is with the display/display connection? Try connecting an external monitor to the laptop and check its display.

crwdns2934105:0crwdne2934105:0

crwdns2853045:0crwdne2853045:0 crwdns2853046:0crwdne2853046:0

crwdns2889612:0crwdne2889612:0 2

crwdns2944067:07crwdne2944067:0:

6 days later, the display, and the Chromebook as a whole, is completely dead. The device shut itself down and I have been unable to power it back on. I attempted to use an external display, but there was no video signal.

crwdns2934271:0Mha 19, 2021crwdnd2934271:0 Dylan Hafley crwdne2934271:0

I would expect such things of a device that has had water dumped on it, but I have treated this with the utmost care. It's only been in my possession for a year, before that it was owned and maintained by my high school, so who knows how it was treated in the 4 years before I got my hands on it?

crwdns2934271:0Mha 19, 2021crwdnd2934271:0 Dylan Hafley crwdne2934271:0

@stevonnie4ever

OK.

The first thing to check with a complete power failure i.e. no lights when charger connected, no start on battery etc, is whether the DC-IN jack (example only) is OK.

If the centre pin of the jack (which carries the +ve voltage from the charger) breaks internally then no charging power from the charger will get through to the motherboard or the battery, so eventually the battery goes flat and won't recharge and the laptop can't be started from the charger either.

You need to access the jack using the manual I linked above and then use an Ohmmeter to check for continuity from the input side of the jack to the wires at the cable plug that is attached to it.

If there is no connection through from the centre pin to the red wires (+ve leg) then you know the pin is broken internally and the jack will have to be replaced as it cannot be repaired. If there is no connection from the outer ring of the jack through to the black wires on the cable plug then the problem is with the -ve leg but the effect is the same i.e. no power.

You have to start somewhere when trying to find out what is wrong and the first thing to do is to check that power is available to the motherboard especially from an external source which I assume is working OK and you can easily test (see p.20 of the hardware manual) because you can't be sure of the status of the internal battery.

crwdns2934271:0Mha 20, 2021crwdnd2934271:0 jayeff crwdne2934271:0

@jayeff the charging light still comes on when plugged in, but it flashes so I'm guessing the connection isn't stable. I had just fully charged it about an hour before it shut off, so the battery isn't dead.

crwdns2934271:0Mha 20, 2021crwdnd2934271:0 Dylan Hafley crwdne2934271:0

After further testing, the charging light doesn't seem to be flashing anymore, so maybe that's a good sign? It only did it when I was trying to use an external display.

crwdns2934271:0Mha 20, 2021crwdnd2934271:0 Dylan Hafley crwdne2934271:0

crwdns2934275:02crwdne2934275:0

crwdns2934285:0crwdne2934285:0