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critical HP
Error Code LED flashes rapidly - Fatal error (all lights on)
Denotes an irrecoverable failure or emergency state requiring external intervention.
? What Causes This
Systemic hardware malfunction triggering critical shutdown processes.
✓ How to Fix It
Unplug and wait 30 minutes before resetting, if persists contact HP support immediately as instructed in the manual.
Source: page 64 of the official manual
From the manual
This error code appears in:
HP Laserjet 1015 Printer