HP Color LaserJet X55745dn - Power On Problem - HP Support Community

JohnKotziasGR · ‎07-31-2026

The printer was connected to a power strip and had been working normally. At some point, it suddenly powered off and has never turned on again. There are no LEDs, including the Formatter board heartbeat LED, and the printer appears to be completely dead. I have also tried a different power cord but nothing.

All of the other devices connected to the same power strip continue to work normally. To rule out a power issue, I connected the printer directly to a wall outlet, but there was still no response. I also tested it in a different room with a different outlet, with the same result.I have also tried a different power cord but nothing.

The printer remains completely off. There is no fan activity, no LEDs, and no signs of life from any part of the printer.

As part of troubleshooting, I first replaced the LVPS, but there was no change. I then ordered and installed a new DC Controller, but the printer still shows no signs of power.

What would you recommend I check next? Should I replace the HVPS as well, or is there something else I should inspect before doing so?

Thanks in advance,

John

Repairatrooper · ‎08-01-2026

Refer to the repair manual here https://kaas.hpcloud.hp.com/pdf-public/pdf_9778320_en-US-1.pdf

It contains troubleshooting steps.

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HP Color LaserJet X55745dn - Power On Problem

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