Lenovo Yoga 7 laptop - flashes the white power led three times quickly

[Blue House Computer Help]

I have a Lenovo Yoga 7 laptop (recent model) that won't start up at all. It just fires up the fans and keyboard backlight, and flashes the white power led three times quickly. Then it shuts of and does it again on loop. Nothing on screen even when hooking up an external monitor to the hdmi port.

Could it be that the power button is stuck pressed down? It's one of those weird side mounted power button that Lenovo do for their yoga's, but it doesn't feel like it has any play when I press in it. I opened the laptop up to have a look, but it would take a lot of tearing down to find out, and they just wanted basic analysis so far.

I tried it with the SSD removed (power light flashes 3 times quickly then 3 times slowly) , and the ram is soldered in, but it didn't do anything more.

Ring a bell? Or any other thoughts?

 

[gadgetfixup]

Smash down on the ram chips while turning it on.

 

[carmen617]

Did you try draining flea power by disconnecting the battery, holding the power button down for 30 seconds, then reconnecting the battery?

 

[Blue House Computer Help]

@carmen617 Yes.

@gadgetfixup Really? Are you pulling my leg?
Can you elaborate? Why might that work?

Anyone else... What would you do? I'm thinking about changing out the power button, And I noticed that it seems that 2 of the corners, including the one with the power switch on, are a tiny bit buckled, like it's been dropped. I wouldn't even bother about it except it's quite an expensive and not very old laptop.

Just so you have a visual in mind, here it is. That oval button just behind the two usb ports is the power button.

Has anyone laid hands on one like this? I'm feeling like zero movement when I press the power button, and I feel like I should feel some, and that that means something is dented in there.

 

[fincoder]

Has anyone laid hands on one like this? I'm feeling like zero movement when I press the power button, and I feel like I should feel some, and that that means something is dented in there.

Time to open it up. You should be able to bypass the power button by shorting its contacts. See if it comes on that way to confirm it's the power button.

 

[NviGate Systems]

English Community-Lenovo Community

Interesting another user posted about the battery LED flashing, and I'm not sure how many LED's there are, as perhaps it's not that, but it could be a low battery warning and the unit can't get enough current to start?

There also cases where the battery management crashes (BIOS Level) and disconnecting battery is the only way to fix it. Some laptops have a pinhole underneath to do this, you put a paperclip in for like 20 seconds and then try again.

I'm not sure but I recall that some laptops these days including Lenovo would not power on if the battery was bad or low/removed. So it's possible it's a battery issue, as in that post above the Lenovo Rep said those flashes were part of the inbuilt management system, and sadly Lenovo doesn't seem to document them. Also, on reddit's r/Lenovo sub, I've seen Lenovo Reps helping users with identifying issues and giving them service steps to try and fix things, might be worthwhile to post there, one of the reps might be able to tell you what 3 flashes mean. I'd start there before ripping it apart.

 

[carmen617]

You haven't mentioned, but have you tried a different charger?

 

[gadgetfixup]

@gadgetfixup Really? Are you pulling my leg?
Can you elaborate? Why might that work?

A power button that doesn't click is suspect.

I wasn't really pulling your leg. So with soldered-on RAM, on newer laptops when the keyboard or laptop flexes, it can crack the brittle solder balls that hold the ram to the mainboard. When you press down on the ram chips you make the connection, and it will boot as long as you have pressure on the chips. It's also a method for determining which ram chip to reball when ram is suspect. Sorin at ERS has several videos showing this method, and I've used it for years when ram is soldered on. It doesn't always work but it's quick and easy enough to do.

If you can't turn it on or interrupt its power on test with the power button I'd look there first. You should feel it click.

Not sure if you have a benchtop power supply but highly recommend one for jobs like this. You purchase a cheap universal charger with a ton of tips for different laptops. Cut the cheap charger off the cord and connect it to a benchtop power supply. Plugging in a laptop to a power supply will give you a ton of information about what is going on. We would be lost without our bench power supply giving us amperage readings during post. We often know what is going on without removing the bottom cover.

A corrupt BIOS is also on the list of suspects. BIOS communicates with EC (SIO) chip on boot, if the data is corrupt, the BIOS sends the corrupt data to the EC and EC doesn't know what to do with it, board reboots. A ton of possibilities really. Many modern laptops have 2 or 3 BIOS chips and the board is dependent on all of them working.

 

[TechLady]

There may be a soft reset hole on the bottom...look for that. If there is one, it can fix many a strange issue, including this stuff.