Laptop won't power on.... Usually. - Lenovo y40

[KennyGsmooth16]

Hey everyone,

To give some back story, I recently replaced my battery and my hard drive (with a faster ssd). My laptop was working perfectly until a few weeks after these upgrades. It is a Lenovo Y40.

So, the first weird thing that happened was, my screen back light just stopped working. You could look really closely and see the computer was running, but couldn't see anything because the back light wasn't on. I powered down the computer, and when I tried turning it back on, nothing happened. After sitting for awhile, it'd let me turn it on. This problem would continue coming back over the next few weeks. I pulled off the back and assured that the battery power cable was plugged in all the way, it is. Now I'm at the point where the computer will sometimes power on, and other times not. This is a huge problem, as I'm a computer science major in school, and I need my laptop. I'm determined it's something wrong with the power delivery. I know it's not the battery, because if I plug in the laptop charger, it still won't power on. If the battery is dead, it should be able to run on power from the wall. Anyone have any ideas? I'd really appreciate some help soon to avoid having to purchase another laptop!

Thanks,
Kyndle

 

[mauxie]

the backlight is often controlled by the lid switch which can be in the lid latch(if it has one)
or in the hinge assembly( wiggle the screen).
also check the options in control panel>power options.
the symptoms of not waking up reliably have often been
reported by people that use the sleep option which is usually
the default. I recommend changing the power button setting
to either shutdown or hibernate. hibernate writes a file to disk
and sets a flag in your master boot record to boot from that
file. it is a boot that picks up from exactly where you left off
except that the time has changed. it has never failed me
on any computer. fwiw

on the power issue, remove the battery before you plug in
the cord, and see if it starts reliably. bad batteries have been
known(admittedly rarely) to interfere with startup.

 

[KennyGsmooth16]

the backlight is often controlled by the lid switch which can be in the lid latch(if it has one)
or in the hinge assembly( wiggle the screen).
also check the options in control panel>power options.
the symptoms of not waking up reliably have often been
reported by people that use the sleep option which is usually
the default. I recommend changing the power button setting
to either shutdown or hibernate. hibernate writes a file to disk
and sets a flag in your master boot record to boot from that
file. it is a boot that picks up from exactly where you left off
except that the time has changed. it has never failed me
on any computer. fwiw

on the power issue, remove the battery before you plug in
the cord, and see if it starts reliably. bad batteries have been
known(admittedly rarely) to interfere with startup.

Thanks for explaining all of that, I will try check out the lid switch. Unfortunately, the symptoms remain. It worked perfectly fine for a few weeks again, so I thought all was well. Just a few days ago, it wouldn't boot again. Now, it seems as though the laptop isn't getting power. I can take out the battery, plug it into the wall, and it still won't boot. That pretty much tells me that the battery isn't the case. It seems as though something is wrong with the power delivery. Maybe a short somewhere? If that's the case, I'm not even sure where to start looking.

Thanks,
Kyndle

 

[mauxie]

the backlight is often controlled by the lid switch which can be in the lid latch(if it has one)
or in the hinge assembly( wiggle the screen).
also check the options in control panel>power options.
the symptoms of not waking up reliably have often been
reported by people that use the sleep option which is usually
the default. I recommend changing the power button setting
to either shutdown or hibernate. hibernate writes a file to disk
and sets a flag in your master boot record to boot from that
file. it is a boot that picks up from exactly where you left off
except that the time has changed. it has never failed me
on any computer. fwiw

on the power issue, remove the battery before you plug in
the cord, and see if it starts reliably. bad batteries have been
known(admittedly rarely) to interfere with startup.

Thanks for explaining all of that, I will try check out the lid switch. Unfortunately, the symptoms remain. It worked perfectly fine for a few weeks again, so I thought all was well. Just a few days ago, it wouldn't boot again. Now, it seems as though the laptop isn't getting power. I can take out the battery, plug it into the wall, and it still won't boot. That pretty much tells me that the battery isn't the case. It seems as though something is wrong with the power delivery. Maybe a short somewhere? If that's the case, I'm not even sure where to start looking.

Thanks,
Kyndle

weak cmos battery(keeps power to the rtc and bios) can cause problems.
if your lappy is Japanese, you can usually reset the bios by pulling the cord
and the battery and then holding the power button for 30 seconds.
this will dump all of your settings in the bios(including date and time)
and may allow the computer to boot. if it works, be sure to reset date
and time so that your browsers don't reject all pages. remember that
all bios settings will revert to default.