I needed to perform this operation because I had a Trezor Model T with a lost recovery seed and a bad display. When I plugged it in, I saw the LCD backlight lit up, but nothing showed on the screen. I decided to fix this Trezor wallet with a component swap of the touchscreen.
Note: If the problem is a broken USB-C connector, you will need to employ a soldering iron.
Step 1: Cut around the Trezor case
You will need to very carefully use a razor blade to cut through the ultrasonic seal holding the two parts of the case together. Be careful especially along the top of the device, as that is where the display ribbon is. Score the entire seam all around the device and push the blade in a few mm.
Step 2: Carefully open the Trezor case from the bottom and push up 45%.
When you open the Trezor, the display and motherboard will be connected by two ribbon cables – for the display and touch panel. Don’t yank out the display or you could tear them. Instead, carefully push up on the motherboard to remove the entire assembly from the bottom of the case.
Step 3: Detach the two ribbon cables.
Use a plastic tool to detach the two ribbon cables holding the display to the motherboard.
Now, swap the broken display with the working display and you’re back in business! I used superglue to glue the plastic case pieces together.
If this doesn’t work, you probably have a broken USB lead. You will need to re-solder the USB connector to the motherboard.
In my case, after I reassembled both Trezors, I found that the bad display magically started working too! It turns out that the display connector has come loose. It would have been enough to tear down the broken Trezor and firmly reseat both display assembly connectors. Try this first!