This video shows how to replace the 4G WWAN card on Latitude 5450 or Precision 3490. Be sure to read and follow the safety guidelines to protect your computer from potential damage and ensure your personal safety. For more information about safety guidelines, see the Owner’s Manual at: Dell.com/Support Before you begin, turn off the computer, and disconnect all the attached peripherals. Before proceeding, ensure your computer is in Service Mode. To enter Service Mode, press and hold the B key on the keyboard, and then press the power button.
Now, the computer will boot up and the Owner Tag information is displayed on the screen. Press any key to proceed. The computer will emit three short beeps and shutdown indicating it has entered the Service Mode. Loosen the eight captive screws holding the base cover in place. Using a plastic scribe, pry the base cover from the palm-rest assembly, starting at the top edge and working your way around to release it from all sides. Now, lift the base cover from the palm-rest assembly. If your computer is unable to enter Service Mode, disconnect the battery cable from the system board. Turn over the computer and open the display. Press and hold the power button for five seconds to ground the computer and drain the flea power.
Turn the computer back over. Using a plastic scribe, pry the 4G WWAN-card shield from the right side recess, releasing it from the frame that holds the 4G WWAN card. Lift the shield off the frame. Now, remove the screw that secures the bracket to both the card and the palm-rest assembly. Lift the bracket off the card and palm-rest assembly. Next, disconnect the antenna cables from the WWAN card. Slide and remove the card from its slot on the system board. Now, let’s install the 4G WWAN card.
Connect the white-and-gray cable to the 'Main' connector and the black-and-grey cable to the Aux' connector on the 4G WWAN card. Next, align the notch on the card with the tab on the card slot labelled WWAN. Insert the card into the slot at an angle. Align the screw hole on the bracket with the corresponding hole on the card and palm-rest assembly. Replace the screw to secure the bracket to both the card and the palm-rest assembly. Finally, align and connect the 4G WWAN-card shield to the frame that holds the 4G WWAN card. If the battery cable was disconnected earlier, ensure that you connect it back to the system board.
Next, align the base cover with the slots on the palm-rest assembly and place it into position. Tighten the eight captive screws to secure it in place on the palm-rest assembly. To exit service mode, connect the AC adapter and press the power button. Please note: The computer will only turn on and exit service mode if the power adapter is connected. For more information about Latitude 5450 or Precision 3490 laptop, go to: Dell.com/Support.