HP laserjet 3390, 3392 all-in-one Manuale Di Servizio
Introduction
This chapter documents removal and replacement of field replaceable units (FRUs) only.
Replacing FRUs is generally the reverse of removal. Occasionally, notes are included to provide
directions for difficult or critical replacement procedures.
directions for difficult or critical replacement procedures.
HP does not support the repairing individual subassemblies or troubleshooting at the component level.
Note the length, diameter, color, type, and location of each screw. Be sure to return each screw to its
original location during reassembly.
original location during reassembly.
Incorrectly routed or loose wire harnesses can interfere with other internal components and can become
damaged or broken. Frayed or pinched harness wires can be difficult to locate. When replacing wire
harnesses, always use the provided wire loops, lance points, or wire-harness guides.
damaged or broken. Frayed or pinched harness wires can be difficult to locate. When replacing wire
harnesses, always use the provided wire loops, lance points, or wire-harness guides.
Removal and replacement strategy
WARNING!
Turn the all-in-one off, wait 5 seconds, and then remove the power cord before
attempting to service the all-in-one. If this warning is not followed, severe injury can result, as
well as damage to the all-in-one. The power must be on for certain functional checks during
troubleshooting. However, the power supply should be disconnected during parts removal.
well as damage to the all-in-one. The power must be on for certain functional checks during
troubleshooting. However, the power supply should be disconnected during parts removal.
Never operate or service the all-in-one with the protective cover removed from the laser/scanner
assembly. The reflected beam, although invisible, can damage your eyes.
assembly. The reflected beam, although invisible, can damage your eyes.
The sheet-metal parts can have sharp edges. Be careful when handling sheet-metal parts.
CAUTION
Do not bend or fold the flat flexible cables (FFCs) during removal or installation. Also,
do not straighten pre-folds in the FFCs. You must make sure that all FFCs are fully seated in their
connectors. Failure to fully seat an FFC into a connector can cause a short circuit in a PCA.
connectors. Failure to fully seat an FFC into a connector can cause a short circuit in a PCA.
NOTE
To install a self-tapping screw, first turn it counterclockwise to align it with the existing
thread pattern, and then carefully turn it clockwise to tighten. Do not overtighten. If a self-tapping
screw-hole becomes stripped, repair the screw-hole or replace the affected assembly.
screw-hole becomes stripped, repair the screw-hole or replace the affected assembly.
Electrostatic discharge
CAUTION
Some parts are sensitive to electrostatic discharge (ESD). Look for the
ESD reminder when removing all-in-one parts. Always perform service work at an ESD-protected
workstation or mat. If an ESD workstation or mat is not available, ground yourself by touching
the sheet-metal chassis before touching an ESD-sensitive part.
workstation or mat. If an ESD workstation or mat is not available, ground yourself by touching
the sheet-metal chassis before touching an ESD-sensitive part.
Protect the ESD-sensitive parts by placing them in ESD pouches when they are out of the all-in-
one.
one.
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Chapter 5 Removal and replacement
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