ThinkPad Universal USB-C Dock (40AY) drops connection and freezes dock when connected to laptop without laptop's AC connected first
by Unusual_Trade5917
The Hardware: Dock: Lenovo ThinkPad Universal USB-C Dock (40AY) Laptop: HP Pavilion 14-dv2000 The Problem: If I plug the dock into the laptop while on battery power, it connects for a few seconds, then completely drops all data and power. Worse, it completely crashes the dock. The dock's white light stays on solidly (indicating computer connection is still established), even if I unplug the USB-C cable from the laptop. I have to switch the wall socket off and on just to reset it. The Workaround: If I plug the laptop’s original HP AC charger in first , and then plug in the dock, it works flawlessly. Once it's connected, I can even unplug the HP charger and the dock takes over, charging the laptop and running peripherals indefinitely without any issue. What I've Already Tried (None of it worked): Updated laptop BIOS and Lenovo dock firmware to latest versions. Disabled USB Selective Suspend and PCIe power saving. Unchecked "allow computer to turn off this device to save power" for literally all usb controllers in device manager. Uninstalled the Windows UCM-UCSI ACPI device, performed a hard 60-second power drain on the laptop, and then reinstalled the Windows UCM-UCSI ACPI device. Didn't work "Bare dock" test where I plugged the dock in with zero monitors or peripherals attached—it still crashed. Tried disabling USB Always On (HP Sleep and Charge). Nope How do I fix this? I'd rather not have to always connect the laptop's AC power first every single time, before connecting it to the dock... submitted by /u/Unusual_Trade5917 [link] [comments]