JDM - 040 L3 and Options buttons pressed constantly

[Daywalk3r]

Hi everyone. I bought two ds4 after water. The largest traces of oxidation were under MCU and bluetooth module. After cleaning, I resolder the MCU, used hot air gun, waited until the balls under the MCU melted and gently shook the microcircuit with tweezers. I did these operations for two ds4. Thereafter the ds4 turned on and was detected by the PC. The only thing is that the l3 and Options buttons are constantly pressed.


 I've checked the buttons for continnuity  - the buttons are working fine. While writing this topic, I connected DS4 to the PC - the problem disappeared. after 10 seconds, the buttons again became constantly pressed. I will be glad to any advice. Thx.

[RDC]

There could be some corrosion inside the buttons giving them just enough internal Resistance for the MCU to detect them as being pressed. Remove them and see how it acts.

[Daywalk3r]

I disassembled the button, cleaned it with isopropyl alcohol, but the button is still pressed.

[wickated]

swap MCU, they are dead.
_{поменяй местами процы, зажатые кнопки переедут вместе с ними}

[RDC]

Could be a mess under the MCU, since it's BGA all kinds of things can get under there that are very difficult to get out without removing the thing.

[Daywalk3r]

Carefully removed MCU. Cleaned up the traces of corrosion. Soldered back. Everything works.
Thanks to all!