Denso BHT-400B-CE - Manual (Page 104)

Running Scandisk through the FLASH folder
If the power to the BHT is shut down when the FLASH folder is being accessed, some broken file
fragments may remain in the FLASH folder so that the free memory space will be decreased.
To remove or clear those fragments, run Scandisk through the FLASH folder.
Initializing procedure
(1) Tap the Scandisk tab and select the Scandisk button.
⇓ ⇑ Select No.
(2) To initialize the memory, tap the Yes button; to return to the
previous menu, tap the No button.
⇓ Select Yes.
Upon completion of Scandisk (it may take a few minutes depending
upon the use conditions of the FLASH folder), the screen shown at
left appears.
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