SOLVED: Lenovo Flex 3 Flashing Power Light But Will Not Power Up

If you have a Lenovo Flex 2 or Flex 3, you may have a situation in which the unit goes to sleep but will not power back up.  Instead the power LED just keeps flashing at you.

Many people believe this is related to Windows 10 but I have read several first hand accounts from people who had the problem with Windows 8.1, so I am unconvinced.  Regardless, it would appear the problem is related to power management settings.

In my case the solution was to pull the battery, wait 2 minutes and then reconnect the battery.  The problem is that in a Lenovo Flex 3, that is not a simple as it sounds because the battery is internal.  Fortunately, it is still not very hard to do:

  1. Unplug the unit from the AC power and all other devices (i.e. USB mouse…)
  2. Turn the unit over and remove all 10 screws
  3. From the corner under the screen near the network and Kensington lock port, use your fingers to pry the back off
    1. I have done this 4 times now, without any damage to my unit
  4. Disconnect the battery connector cable from the motherboard
    1. In my case my fingernails just would not do it, so I used a tiny ‘flat’ screwdriver to pry each end of the black plastic connector out of the metal header
  5. Let it sit for a few minutes (2?) so that everything on the motherboard drains.
  6. Slide the battery connector back into the header
  7. Press the power button and see what happens
    1. If it powers up, put the back on and screw it down, your done
    2. If it does not power up, disconnect the main battery again, pull the BIOS battery, let it sit for 5 minutes (to drain) then plug the unit into the AC power adaptor (i.e. do NOT reconnect either battery) and power up
      1. If this works, power down the unit, reconnect both batteries, put the back on and screw it down, your done
      2. If your Flex 3 still does not work, you likely need to put everything back the way it was, call Lenovo for warranty support and make sure you don’t tell them you pulled it appart because they might void your warranty (or buy a battery off eBay)

View Comments

  • Can anyone tell the solution of the question which MrWizard Usa raises. (Same situation here) Please! Thanks in advance..

    • I am an IBM (retired) Systems Tech. While the suggestions of unplugging the battery and pressing the power button do solve similar issues where the BIOS has got messed up and locks the system. Machines that do not respond to those steps should try the following, It works in 90 percent of the cases if the mother board or processor has not failed.
      The 3 blinking lights at the power supply on a Lenovo signify that the system has halted in an error state.
      Most of this is caused by an overheat condition on the graphics chip or the CPU.
      After gaining access to the main board, disconnect the power supply and the wires from the battery to the Main Board,
      Using all static grounding procedures the technician should carefully remove the screws holding the heat sink to the main board. They will notice a gray paste usually smeared all over, this is the problem, during assembly they put too much on and it shorts out or flows away from the surfaces its supposed to cover and in many cases it turns hard and no longer works. Note if the Graphic Chip uses a soft Foam cover DO NOT REMOVE IT OR TAKE IT OFF THE COPPER HEAT SINK.
      Carefully using only your fingernail chip off the paste and use a vacuum cleaner to remove the debris, remove the gray stuff from both the heat sink and the processor and graphic cards. when everything is completely clean wipe the surfaces with a cotton swab dipped in alcohol to remove any grease. Wait till it evaporates.
      You will need to find or purchase some heat sink paste, I recommend ArctiC Silver Ceramique. Put a tiny dab on the black shiny surfaces that are the surface of the CPU and the Graphic Chip if it was also with the old gray paste, If the Graphics chip had a soft foam cover looking item DO NOT put any replacement paste on it.
      Carefully re assemble everything with the correct screws. Reconnect the battery wires and any other wires or flat cables that you disconnected, I recommend using your phone to take a picture before you start and after you are done compare to make sure everything is reconnected properly.
      Re assemble the case back and plug in the external power start the laptop .. It should start normally. At this time if necessary re install windows or what ever OS you had before if it was damaged.

    • Unfortunately I can tell you that 2 of the 3 Flex 3's that I work with have now had broken motherboards. Specifically, if you look at where the power connector is on the right side, you will notice how thin the plastic is around it and it appears to not be strong enough to deal with the pressure opening/closing the screen puts on it. The last Flex3 I deal with is only still running because I pried up the grey rubber feet and tightened all the screws. If draining the battery does not resolve your issue, look for a cracked motherboard about 1" from the 'top' (where the keyboard base attaches to the screen) about where the power connector is :(

  • Unplug the battery and remove the Bios Battery work for me, but i don´t know which one was the really solution, recommend do it both. Thanks you very much. Lenovo Flex 3-1580

  • Where is the battery connection port and cable that I can disconnect the battery on my lenovo flex 2 14, as I have looked everywhere for it, but cannot find it.

    • I only have Flex 3's so I cannot provide more specifics HOWEVER I suggest you try to physically remove the battery and the cable connection should become apparent quite quickly. I hope this helps.

  • I have a flex 3 and my son yanked it down by the cable. The cable is bent but I did fix it. I was able to run through all this and after putting the BIOS battery and main battery in, the fans spin and lights come on for a second or 2 then go out, back to blinking power lights. Any thoughts?

  • Thanks very much. We followed the directions and disconnected the battery and waited 5 minutes. After that, reconnected battery and it powered up and worked fine.

    Any ideas on how to prevent this from happening again?

    • Unfortunately, I don't know what the root cause is, so I can not say what you need to do to prevent it. Personally, I keep flashing my BIOS' and hoping the issue goes away.

  • The battery is a little different on my Lenovo Flex 2 15. I had the same problem and fixed the same way (unplugging the ac adapter and disconnecting the battery from the motherboard for a minute), but the connector is close to the lid. The battery is so small I failed to see it the first time.
    REMEMBER you have to take the keyboard out to unscrew a few screws - check Youtube videos on disassembling Flex 2. If you don't do that you'll probably gonna break the bottom lid.

  • My Flex 3 problem is similar in the fact that my power button is flashing, but my system will boot. However, when the system boots the keyboard is messed up and will only display 6s and 1s from all keys. For example pressing numlock will display a 6. The onscreen keyboard works, but the wifi will not turn on and there many other oddities. I have found if I turn the machine on and let it die a slow death for a day while the battery discharges it will work again. I believe I have turned hibernation off so I'm not sure what the issue is. I'm hoping someone comes up with a solution as this is a pain!

  • The Flex 3 has always on USB ports so if you have devices connected that draw power this would kill the battery over time if the computer is not plugged in.

  • Hey, do you think replacing the battery would fix this issue permanently? I have a Flex 3. Also do you know of any USB devices, that drain laptop power even when in sleep/standby/powered down?

    • It has occurred to me, but I just don't know. I THINK the power up / flashing LED problem has more to do with the way Windows is handling Sleep Modes on these Lenovo laptops, but again... I don't know.

This website uses cookies.