So we haven't used our Tello for a while but recently got excited and decided to charge it up, but regardless of what USB power source we connect to it, its completely dead. If we remove the battery and connect the Tello to USB, there's just nothing there either, so its not the battery at fault it seems, but the Tello itself.

Any hints, tips or suggestions to bring it back to life? We've tried holding the power button before connecting USB, keeping it held in after, everything basically, but just nothing works or gives any lights.

Dear customer,
We are so sorry to hear your issue. Do you have another battery? Please change another battery and try to re-upgrade the firmware.
Please press and hold the Power Button for 5 seconds when the Tello is powered off and release it when the green indicator turns off. Then the indicator will pulse red. Connect to the Tello's Wi-Fi and go to Setting - more - firmware version to upgrade the firmware again. After that, please confirm if the issue still persists.
If the issue still persists, please contact us via support@ryzerobotics.com.
I hope my answer can help you. Thanks a lot.

RYZE Posted at 6-4 18:23
Dear customer,
We are so sorry to hear your issue. Do you have another battery? Please change another battery and try to re-upgrade the firmware.
Please press and hold the Power Button for 5 seconds when the Tello is powered off and release it when the green indicator turns off. Then the indicator will pulse red. Connect to the Tello's Wi-Fi and go to Setting - more - firmware version to upgrade the firmware again. After that, please confirm if the issue still persists.

I only have the one battery, but shouldn't the Tello connect to the PC via USB without a battery installed anyway?

sergeant Posted at 6-5 08:06
I only have the one battery, but shouldn't the Tello connect to the PC via USB without a battery installed anyway?

Sorry，Tello doesn't have the ability to connect to PC via USB. It can only upgrade the firmware via Tello APP while it is power on.
If the problem still persists, could you please contact us via support@ryzerobotics.com. It may need to send to us and have a test by our engineers.
Thanks a lot.

Hope you get it fixed!

Fingers crossed its in the air soon enough

Hope it goes well.