Lenovo Yoga pulsing white power LED

[timeshifter]

Remember my neighbor's Lenovo where I was wondering about putting a heat sink on a replacement SSD?

https://www.technibble.com/forums/threads/what-do-you-think-about-adding-heat-sinks-to-ssds-on-laptops.89701/

Well, the plot thickens. To get this out of the way, I told him I wasn't going to do any of the heat sink ideas.

The machine is a Lenovo Yoga C740-15IML Model Name: 81TD. Decent machine, i7 I believe, about two years old. He told me it's crashing, unstable, etc. It sounds like hardware during our initial conversations. I agree to have a look at it. I boot it from an external WinPE drive. It runs for days unscathed. So I tell him that I'd like to try a new SSD which would include a clean Windows install, feel like there's a decent chance the system may be OK.

So, tonight I did the SSD swap. I did notice some stains that looked like it had had a tiny bit of liquid, maybe coffee. Now, before the alarm bells go off, look at the pic

http://infotime.com/images/justinlenovo.png

I only see this by the battery, the main motherboard looks like it's never been touched by this. Maybe it's liquid damage, maybe not.

Anyway, I install the new SSD. Put it back together, everything seems normal. I start the install of Windows 11. It boots, I pick the drive in the installer, it starts doing it's thing. Easy peasy. Then the lower half of the screen goes black. Then the visible portion of the screen slowly darkens and fades to black while the install seems to still be going.

I was doing the install on battery power. Do'h. I noticed the battery level was at 61% earlier before I opened it up, so normally I'd expect to be able to do an install on an all solid state machine just on battery power (not that I'd do it on purpose).

So now, I can't get it to show anything on the screen. I've done all kinds of resets that I can think of like disconnecting the battery, the CMOS battery, holding power, etc. And I'm trying this with the power plugged in or whatever.

Still no video or life. The LED on the power switch will come on then go off after a few seconds. My USB drive - iODD - will light up then go dark. I tried removing the new SSD, installing the new SSD, etc. Nothing seems to help.

Are there any other resets or tricks I can try or is she a gonner?

 

[Computer Bloke]

The straight edges on the stain on the battery look as if a sticker's been removed. I don't think it's liquid damage.

Is the power LED pulsing in a distinctive pattern? It might be that the machine is trying to tell you something.

 

[phaZed]

If you remove the SSD, will it boot to BIOS?

 

[timeshifter]

If you remove the SSD, will it boot to BIOS?

No. Behavior is the same with the new SSD, with no SSD and with the original SSD reinstalled.

 

[timeshifter]

The straight edges on the stain on the battery look as if a sticker's been removed. I don't think it's liquid damage.

Is the power LED pulsing in a distinctive pattern? It might be that the machine is trying to tell you something.

Good catch! There is some kind of tape on the underside of the case that lines up with that. There's also some other gunk nearby that made me think it was liquid, like dried coffee, but it might just be melted adhesive gunk.

I did have the battery disconnected in the photo, but it was connected and disconnected several times in the process.

Is the power LED pulsing in a distinctive pattern? It might be that the machine is trying to tell you something.

I turn it on and the LED stays on for 12.5 seconds, then goes off for 12.5 seconds, then repeats that pattern indefinitely until I hold the power button down to get it to shut off.

 

[Computer Bloke]

That light pattern definitely isn't a blink code but it could be sort-of consistent with a very depleted battery. At this point I'd put it all back together, plug it in, make sure power's getting to it, and leave it all until the next day. You need to rule out battery/power issues before going any further.

Incidentally, are you able to check the voltages on that internal power connector? If so, that would be the next thing to look at (once you're sure the battery's had a chance to charge, of course).

Edited to add: What do the fans do when you try to switch the machine on? And has the CPU heatsink been removed at any point? (I'm sure you can see where I'm going here!)

 

[timeshifter]

At this point I'd put it all back together, plug it in, make sure power's getting to it, and leave it all until the next day.

Good idea, that’s what I’m doing. It had been sitting for a long time unplugged.

 

[nlinecomputers]

Part of the problem is the battery is not fully plugged in. I know because I have one on the bench right now with the same blinking light problem. You'll need to fully plug in the battery and then hit the battery reset button aka the novo button.

 

[nlinecomputers]

I'll also add that those Lenovos are stinking piles of crap. Constant trouble.

 

[phaZed]

I'll also add that those Lenovos are stinking piles of crap. Constant trouble.

I would have to agree. I love Lenovos in general and have had quite a few of them... but man, those YOGA's seem to screw up a lot - and it's usually a MB.

 

[nlinecomputers]

 

[nlinecomputers]

I would have to agree. I love Lenovos in general and have had quite a few of them... but man, those YOGA's seem to screw up a lot - and it's usually a MB.

Lenovos are on both ends of the spectrum. Thinkpads are great some of the best PCs made. IdeaPads are opposite the worst PCs made. Yogas
are on the IdeaPad side of the scale, except for the few that are also branded as Thinkpad. Not the case with this one as it only a Yoga so it is an Ideapad without the Ideapad label.

 

[timeshifter]

I was about to report that all is well, then it was not.

So I let it charge overnight. Started out and it looked OK. Light was slow pulsing when I returned this morning. Swapped in the new SSD, booted, installed Windows, running OOBE, then the lower third of the screen went black and it all starts to fade. Right now I'm staring at a screen that seems to have its backlight on but nothing displayed, my iODD is still powered up by the USB port, power LED is solid.

Part of the problem is the battery is not fully plugged in. I know because I have one on the bench right now with the same blinking light problem. You'll need to fully plug in the battery and then hit the battery reset button aka the novo button.

Not familiar with the novo button. Can you tell me more please?

edit: or maybe you already did with that video posted above? (I'm headed out the door will watch later)

 

[phaZed]

Not familiar with the novo button

It's a little pin-hole switch to essentially BIOS boot/reset

Where can I find the OneKey Recovery (Novo) button on ideapad laptops - Lenovo Support US

support.lenovo.com

IIRC the YOGA's have it on the bottom cover (the hole), towards the middle of the machine.

 

[timeshifter]

Could that be his overall problem? System crashing, unstable, etc.

 

[phaZed]

Sounds like a bad board, to me.

 

[fincoder]

There is some kind of tape on the underside of the case that lines up with that. There's also some other gunk nearby that made me think it was liquid, like dried coffee, but it might just be melted adhesive gunk.

That's definitely a sign of liquid spill, a drink like coffee, cola or beer. The straight edge is caused by the sticker you mention preventing the spread of the liquid, not causing the stain. The sticker is probably a pad to fill the gap between battery and bottom panel.

It doesn't appear to have affected the main board and other components, but you can't be sure without checking the other side of the main board.

Have you tried turning it on with battery disconnected? Re-seated the LCD cable?

 

[HCHTech]

Moisten a q-tip and swab that stain, then smell it - coffee is distinctive, so is beer. I love calling the customer and asking "So, when did you spill the beer on it?" Haha.

 

[tf76]

Yeah, my daughters Lenovo Yoga 7i came with a bad motherboard. Got the motherboard replaced within the 12 months warranty.

 

[timeshifter]

I returned the laptop the other day and told him that I couldn't fix it, due to the unpredictable damage from liquid, etc.

He emailed me two days ago:

"I looked inside again at the (most likely coffee) spill in the laptop and noticed some in the area of the audio jack board and the speakers. After unplugging both from the motherboard and reinstalling the SSD, I have been using it lightly (youtube/web browsing mostly, still a little afraid to push it too hard) without issue for several hours a day since getting it back. I plugged in a usb c monitor today as a second display too and it seems fine. "