HP Compaq Presario,Presario CQ42-121 Maintenance And Service Manual page 69

2. Loosen the 2 Phillips PM2.5×5.0 captive screws (1) that secure the mini-card compartment
cover.
3. Lift the cover off the computer (2). The mini-card compartment cover is included in the plastics
kit, spare part number 600190-001.
4. Disconnect the two WLAN antenna cables (1) from the WLAN module.
5. Remove the Phillips PM2.0×3.0 screw (2) that secures the WLAN module to the computer. (The
edge of the module opposite the slot rises away from the computer.)
6. Remove the WLAN module (3) by pulling it away from the slot at an angle.
CAUTION:
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 computer functionality, and then contact technical
support through Help and Support.
NOTE:
WLAN module slot.
Reverse this procedure to install a WLAN module.
ENWW
To prevent an unresponsive system, replace the wireless module only with a
WLAN modules are designed with a notch (4) to prevent incorrect insertion into the
Component replacement procedures 59