Thunderbolt 3 troubleshooting FAQ's

Document ID: 4016286


Posted Date: 2018-11-02


Distribution: View Public Website


Applicable Models
Thunderbolt 3 PA5281U-1PRP




Many issues related to connectivity with the Toshiba Thunderbolt 3 dock can be resolved easily by reviewing the following Videos and FAQ's

Click here to find the Users Guide and Quick Start guide

Click here to view a video on troubleshooting the Thunderbolt 3 dock

First Step

Get to know the status LED's on the front of the Thunderbolt 3 dock

Always ensure you are updated to the latest BIOS on the Toshiba laptop by going to



When connected to the laptop both of the LED lights on the front of the Thunderbolt 3 dock are turned ON but some or all of the connected devices do not work

Check Thunderbolt 3 software setting in the task bar. See this support bulletin for more detail:

External HDMI monitor does not work when connected

Check the HDMI plug connection to the Thunderbolt 3 dock to ensure the HDMI is inserted all the way in. Depending on the HDMI cable used sometimes the connector feels like it is inserted all the way but ends up being only partially inserted. See this support bulletin for more detail:

The AC power indicator light on the Thunderbolt 3 dock does not turn on after connecting the AC power adapter
  1. Check the AC power source to the AC adapter
  2. Unplug the AC adapter from the Thunderbolt 3 dock for 30 seconds and then reconnect
  3. Press the power button on the side of the Thunderbolt 3 dock
The DC power delivery indicator light does not turn on after connecting the Thudnerbolt 3 USB-C cable to the laptop
  • Check to ensure you are using a laptop with a Thunderbolt 3 USB-C connector and USB-C Thunderbolt 3 cable as shown below indicated by the Thunderbolt icon
  • Unplug the USB-C Thunderbolt 3 cable from the back of the Thunderbolt dock and then reconnect
The Thunderbolt 3 dock will not charge my laptop via USB-C port
  • Ensure that you are connecting to a USB-C charging port on the laptop by reviewing the users guide for the laptop
  • If you are trying to connect to an Apple laptop check the power charging spec on the laptop as the Thunderbolt 3 dock maximum power charging capabilities are limited to 45 watts




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