HP LaserJet Enterprise M552 - Tools for troubleshooting; Individual component diagnostics; Tools for troubleshooting: LED diagnostics; Understand lights on the formatter

Tools for troubleshooting
The section describes the tools that can help solve problems with the printer.
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Individual component diagnostics
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Diagrams
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Internal test and information pages
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Control-panel menus
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Control panel message document (CPMD)
Individual component diagnostics
Tools for troubleshooting: LED diagnostics
LED, engine, and individual diagnostics can identify and troubleshoot printer problems.
Understand lights on the formatter
Two LEDs on the formatter indicate that the printer is functioning correctly.
1
2
1 Heartbeat LED
2 HP Jetdirect LEDs
Heartbeat LED
The heartbeat LED indicates that the formatter is functioning correctly. While the product is initializing after it
is turned on, the LED blinks rapidly, and then turns o. When the product has nished the initialization
sequence, the heartbeat LED pulses on and o.
The following table describes the heartbeat LED operation while the product is executing the rmware boot
process.
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