Laptop Battery Emergency Reset

TTony

Sharing this in case it ever helps anyone else ...

My main PC is a Thinkpad laptop which sits on my desk, connected via USB-C to a dock which provides power, link to external monitor, additional USB3 ports, etc.

This morning, switched laptop on, and external display didn't wake up.  Odd. 

• Maybe it's switched itself to another input?  Checked, reset, and confirmed it's on the right input but not receiving a signal from the dock.
• Connect laptop direct to monitor, and all is OK, so cable is undamaged and laptop is outputting a signal.
• Unplug, switch dock off and leave for a few mins, reconnect the peripherals and switch back on.  Still no monitor signal.
• Hmmmm.
• Then I notice laptop battery level is falling and is below the level that should trigger it to charge.  Hmmmm some more.
• Check battery charge settings, and it should certainly have started charging as it's now <50%.
• Try a different USB-C cable from dock to laptop, still no change.
• Run Lenovo diagnostics and there are a few driver and firmware updates recommended.
• Install, reboot, and battery is still not charging.
• Hmmm some more.
• Google for local laptop repair options.
• Let's make sure all docs/settings are backed up to date.
• Then let's remove any sensitive docs completely.
• That hits the battery level, now <30% after some intensive backup activity.
• Try the thunderbolt port instead, still via the dock, and still no battery charging.
• Dig out the separate AC adapter, plug that in, and still no battery charging.
• One last Google search reveals an "emergency battery reset button".
• Switch laptop off, insert pin into (well hidden) reset button recess, hold for 7secs, release and switch back on.
• Hold breath whilst laptop boots.
• Login, still holding breath.
• Check battery status, and it's charging again.
• Working both through dock and adapter.
• Switch off, leave it charging, and walk away for an hour or so.
• Switch on, and battery is restored.

So, if you ever have an issue with charging/powering a laptop, check for the presence of an emergency reset button.  Or check now, so you know in advance.