This is a Samsung A02S, first let’s check out its WIFI.
Connected, no Internet.
Power off and turn around the phone. Unbolt the screws on the logic board bracket, remove the logic board bracket.
Apply stickers onto the cameras.
Remove the battery connector, the charging connector and the display connector. Remove the logic board and the rear cameras module.
Observe the front cover and the back cover of the logic board, no water-damaged trace.
Put the logic board onto the PCB holder, heat the WIFI chip shielding cover and take it off(330℃,30 wind).`
Measure the diode reading of the capacitor near WIFI chip with a multimeter, 0V.
Obviously, the power-supply circuit is cut-out.
Apply some rosin around WIFI chip with this atomizer, connect it to 4V voltage.
We can see the rosin over here melting.
Take off this capacitor with a hot air gun, measure the diode reading of this circuit again. 398V, back to normal.
Remove the logic board, install it. Connect all cables, power on. WIFI connected. Settings-WIFI connected.
Open a page and see if it works, connected successfully.
Power off. Remove the logic board, and put it onto the PCB holder. Heat the WIFI chip shielding cover and install it.
After it’s cooled down, install the cameras module and the logic board.
Connect all cables. Remove the camera stickers. Install the logic board bracket and the screws on it.
Power on, test its WIFI, connected successfully.
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