HP ProBook 450 G2 Notebook PC HP ProBook 455 G2 Notebook PC Maintenance and Service Guide

RTC battery, HP 455 models
Description Spare part number
RTC battery 738824-001
Before removing the RTC battery, follow these steps:
On HP 455 models, you access the RTC battery without removing the system board.
1. Shut down the computer. If you are unsure whether the computer is off or in Hibernation, turn the
computer on, and then shut it down through the operating system.
2. Disconnect all external devices connected to the computer.
3. Disconnect the power from the computer by first unplugging the power cord from the AC outlet, and
then unplugging the AC adapter from the computer.
4. Remove the battery (see
Battery on page 43).
5. Remove the following components:
a. Service doors (see
Service door on page 44).
b. Hard drive (see
Hard drive on page 46)
c. Optical drive (see
Optical drive on page 50)
d. Keyboard (see
Keyboard on page 56)
e. Top cover (see
Top cover on page 64)
Remove the RTC battery:
1. Using a flat tool, pry the battery out of the socket (1).
2. Remove the battery from the socket (2).
Reverse this procedure to install the RTC battery.
Component replacement procedures 67