Oki LD670 User Manual page 178

(2) Select "CLEANING" as your option.
Press the FEED switch briefly (one second or less) three times to
move to "CLEANING."
Cleaning
Sensor Adjustment
Setup
Test Print
End
Sample Print
Data Analysis
Cleaning
Sensor Adjustment
Setup
Test Print
Special Mode
Usage
Item Selection
Item Decision
(3) Press and hold down the FEED switch for one second or longer to accept
the selection.
The printer prints the following when you accept the selection of
"CLEANING":
↑
↑
↑
Selection Item
Please push the feed switch short.
Please push the feed switch long.
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