Panasonic HG-T Series User Manual page 83

<Key lock release>
1.
While key lock is enabled, hold down the
"OFF" appears in the digital display section / MAIN (white) and lock is released.
(Note): Even when auto key lock is enabled, you can use the above operation to release the lock.
WUME-HGT-3
key and key simultaneously for 2 seconds.
Basic Usage
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