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error HP
Error Code Supplies LED blinks
Denotes problems or warnings regarding the toner cartridges and imaging drums, such as error or malfunction.
? What Causes This
Issues relating to consumables; could involve jams, low supplies, incorrect installation.
✓ How to Fix It
Follow indicated instructions on control panel for resolution. Replace parts if necessary.
Source: page 4 of the official manual
From the manual
This error code appears in:
HP Laserjet Pro M203 Printer