This guide will help you with the process of replacing the Wi-Fi PCI Card in your device.
Unscrew the two screws using a Phillips #0 screwdriver.
Use a spudger to lift the back cover and remove it from the device.
Unplug the two wires that are on the Wi-Fi PCI card (white & black).
Unscrew the single screw in front of the Wi-Fi PCI card using the Phillips #0 screwdriver.
Remove the Wi-Fi PCI card from the device.