ThinkPad P52s charging/Thunderbolt issues

Aug. 3, 2019, 10:55 p.m.

This morning after waking my ThinkPad P52s (Windows 10 x64) from sleep the following happened:

  1. The "A Thunderbolt controller has experienced a problem and cannot connect to devices or other computers until new firmware is installed" dialog box popped up several times. However, it no longer shows up. I believe (after some googling) this means the controller went into "safe mode" for some reason and will only accept firmware updates now.
  2. Both USB-C ports stopped working properly (peripherals connected to either of those ports are not functioning). I was able to use those ports just fine few days ago.
  3. The 65W Lenovo power adapter is now detected as "15W USB-C power" instead of "AC power". This results in batteries charging only when power consumption does not exceed 15W (i.e. when laptop is powered off or idle). Most likely due to the same reason the following message is now shown during every reboot: "The connected AC adapter has a lower wattage than the recommended model which was shipped with the system. To boot with the AC adapter, please connect the AC adapter which was shipped with the system. Press Esc to continue."

Thunderbolt controller is enabled in BIOS. "Thunderbolt in BIOS Assist Mode" is disabled.

It looks like Power Delivery is not being negotiated between the power adapter and the laptop due to (malfunctioning?) Thunderbolt controller.

What I've tried so far:

  • Plugging power adapter to both USB-C ports with the same result (see 3. above)
  • Updating OS to the latest version using Windows Update
  • Applying all the updates in Lenovo Vantage (including BIOS update to 1.22)
  • Re-installing the latest available version of Thunderbolt Software (17.4.78.500)
  • Re-installing and running the latest version of the Thunderbolt Firmware Update Tool (17.0.0.1-N27TF15W). The tool is not able to detect any Thunderbolt controllers and exits with the following message: "No active Thunderbolt(TM) controller found in the system or Thunderbolt(TM) software is not present in the system. Make sure you have Thunderbolt(TM) software installed. Then connect Thunderbolt(TM) device and retry." I can see it tries to use the "force power" feature to wake the controller without any success.
  • Tried booting into Ubuntu Linux and triggering "force power" myself with echo 1 >/sys/bus/wmi/devices/86CCFD48-205E-4A77-9C48-2021CBEDE341/force_power, but the controller does not show up under /sys/bus/thunderbolt. lspci just hangs for an unknown reason.
  • Disconnected the power source, took out the removable battery and disabled the internal battery in BIOS. Also tried disconnecting the internal battery by inserting a paperclip into the emergency-reset hole on the bottom of the laptop.

Unfortunately I do not have any true Thunderbolt peripherals (only USB 1.0/2.0 with USB-C adapter cables) to plug in an see if that will wake the Thunderbolt controller up.

It is unclear whether it is a hardware issue or some catch 22 with controller not waking up because it wants the firmware update and firmware update not being applied because the controller is not waking up.