Backdoor won't open on 2005 Toyota sequoia?
Removed the back panel from inside staring from top to bottom of the plastic, and you will be able to open. Then replace the back door handle.
If the handle is broken, then you'll have to manually open it. If the locking mechanism is frozen, you will have to manually open it. Generally that means pulling the back panel off and pulling the latch cables by hand. Sequoia forums have detailed information on how to remove the rear panel - fairly simple.