LG T1300DPS Service Manual page 28

Automatic detection of time to clean Tub
After Power On button pressing, if is blinking in the display, it is the time for Tub Cleaning.
If you want to skip the Tub Clean, press option buttons to select desired cycle.
After performing tub clean, will disappear until next cleaning time.
Tub Clean time is detected automatically as per the usages of washer (Generally once after 30 usages)
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