HP ProBook 640 G1, 645 G1, 650 G1, and 655 G1 Notebook PCs - Maintenance and Service Guide

2. Remove the memory module (2) by pulling the module away from the slot at an angle.
Reverse this procedure to install a memory module.
WWAN module (select models only)
Description Spare part number
HP hs3110 HSPA+ Mobile Broadband Module 723895-001
HP lt4111 LTE/EV-DO/HSPA+ Mobile Broadband Module 704030-001
HP lt4112 LTE/HSPA+ Mobile Broadband Module 704031-001
CAUTION: To prevent an unresponsive system, replace the wireless module only with a wireless module
authorized for use on the computer by the governmental agency that regulates wireless devices in your
country or region. If you replace the module and then receive a warning message, remove the module to
restore device functionality, and then contact technical support.
Before removing the WWAN module, follow these steps:
1. Turn off 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 the power from the computer by unplugging the power cord from the computer.
3. Disconnect all external devices from the computer.
4. Remove the battery (see Battery on page 56).
5. Remove the service cover (see Service cover on page 57).
Remove the WWAN module:
1. Disconnect the WWAN antenna cables (1) from the terminals on the WWAN module.
Component replacement procedures 65