HP ProBook 6550b HP ProBook 6455b, 6555b, 6450b,and 6550b Notebook PCs - Maint - Page 100

WWAN module Description HSPA EV-DO WWAN module Spare part number 531993-001 CAUTION: The WWAN module and the WLAN module are not interchangeable. To prevent an unresponsive system, replace the wireless module only with a wireless module authorized for use in 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. 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 79). 5. Remove the wireless module compartment cover (see WLAN module on page 88). Remove the WWAN module: 1. Position the computer with the front toward you. 2. Disconnect the WWAN antenna cables (1) from the terminals on the WWAN module. NOTE: The red WWAN antenna cable is connected to the WWAN module "Main" terminal. The blue WWAN antenna cable is connected to the WWAN module "Aux" terminal. 3. Remove the two Phillips PM2.5×6.0 screws (2) that secure the WWAN module to the system board. (The WWAN module tilts up.) 92 Chapter 4 Removal and replacement procedures