HP ProBook 450 G4 Notebook PC and HP ProBook 455 G4 Notebook PC - Maintenance and Service Guide

Power button board
Description Spare part number
Power button board assembly 905754-001
Power button board cable (included in Cable Kit) 905769-001
Before removing the power button board, follow these steps:
1. Shut down the computer. If you are unsure whether the computer is o or in Hibernation, turn the
computer on, and then shut it down through the operating system.
2. Place the computer in “Battery Safe mode” (Battery Safe mode on page 32).
3. Disconnect all external devices connected to the computer.
4. Disconnect the power from the computer by rst unplugging the power cord from the AC outlet, and
then unplugging the AC adapter from the computer.
5. Remove the following components:
a. Service door (see Service door on page 33)
b. Optical drive (Optical drive on page 34)
c. Hard drive (Hard drive on page 36)
d. Keyboard (see Keyboard on page 45)
e. Top cover (see Top cover on page 52)
Remove the power button board:
1. Position the top cover upside-down.
2. Disconnect the cable from the connector on the board (1).
3. Remove the Phillips PM2.0×3.0 screw (2) that secures the board to the top cover.
4. Lift the left side of the board (3), and then pull the board out and to the left to remove it from under the
tabs (4).
58 Chapter 6 Removal and replacement procedures for Authorized Service Provider parts