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Hi there, I have a Lenovo ThinkPad X1 Carbon 6th Generation. It is an awesome device and it used to work flawlessly. Recently, I am facing the problem that the laptop, when shut down, refuses to boot after pressing the power button. Instead of booting, the power button and keyboard lights briefly flash, the fan turns on, spins at most 1-2 seconds, and everything turns off again. When I keep hitting the power button often enough, like 20 to 100 times, the procedure repeats and at some point the laptop boots normally and everything is fine. I also noticed that very seldomly, when the laptop is in standby, it turns off and then refuses to boot, too. Besides that, the laptop works perfectly, once booted and there is no other problem at all. I tried to search on Google but could not find any matching error description. Are there any suggestions on your side what the cause might be, how to debug this, and how to fix this? Thank you very much in advance!

Hi @mrbuuuffed , Try disconnecting the main battery and the coin cell battery in the laptop and then press and hold the laptop’s Power On button for a full 30 seconds and then release it. Here’s the hardware maintenance manual for the laptop. Go to p.70 and p.78 to view the necessary pre-requisite steps and then the procedure to remove the battery and the coin cell battery respectively.. Whilst you have the coin cell battery out, measure its voltage. If it is <2.5V DC replace it. The part number for the coin cell battery is 01HY008. Search online using the part number only in the search box of your browser, to find suppliers that suit you best. Reconnect the coin cell battery and the main battery, re-assemble the laptop, connect the charger and try turning it on. If it turns on there may be a message about the date and time being incorrect. This is normal as the BIOS has been reset to its factory default settings. Once the date and time have been corrected the message won’t appear the next time the laptop is started. Also if you altered any user definable settings in BIOS to suit your particular operating requirements they will have to be set again. Update (05/05/2022) @mrbuuuffed2 You just measure across the coin cell battery plug’s red and black wires. If the plug is narrow sometimes inserting thin wires into the plug and then connecting to them works. Although this battery is not the problem now, as performing the refresh should have reset the BIOS if it were a corrupted BIOS problem that you’re having with the laptop and it should have started. I’m now wondering if you have a faulty power on button. IF the motherboard is model number NM-B481 REV: 1.0 (printed on motherboard) then here’s an image of the lid switch connection. Use an Ohmmeter to check that when pressed there is an earth on pin 3 and that it is not there when the button is not pressed i.e. sticking contacts perhaps. Disconnect the battery when trying this If it is OK then here’s a link to the schematics that may help. Again this is only applicable if the motherboard’s model number is the same as for your motherboard. If not what is the model number of your motherboard?

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That can either be a motherboard issue, dead CMOS battery or simply a corrupted CMOS RAM screwing with the bootup. Dells are also easy to corrupt, so I’ve scored cheap Dells I have no business owning for what I paid ($140 for a i5-8350U listed as an 8250U LG IPS without RAM/SSD) and all I needed to do was remove the CMOS battery and keep the primary disconnected until I seen it boot. No replacement was done. I wasn’t expecting IPS for $150, much less LG IPS. That was a big deal with Samsung out of the TFT game (they were always my budget IPS favorite - losing them was kind of a bummer). All we have left is BOE and LG for TFT LCDs, since Samsung ships OLED laptop screens now, and QLED desktop monitors. Even if the laptop was hosed for $150, the LG IPS display paid for it because I could drop it into a BOE laptop, or a TN 768p which is otherwise well equipped. These are super easy too (but not as easy as my $150 Dell) – you need to remove the main battery to get to the CMOS battery if you need to completely remove it, but it is right there. Refer to this guide: Lenovo ThinkPad X1 Carbon 6th Gen Battery Replacement - iFixit Repair Guide