warning HP

Error Code Three quick amber flashes in the center of the light bar

Currently disabled button is pressed.

? What Causes This

An attempt to use a feature or button that has been disabled on the printer control panel

How to Fix It

Identify and re-enable the feature if necessary in 'Printer Settings' or through the HP Smart app interface. If feature remains disabled consult service manual for further instructions.

Source: page 14 of the official manual

From the manual

Manual page 14 — HP error Three quick amber flashes in the center of the light bar

This error code appears in:

HP Envy 6400E All-in-One Series Printer