How to clean the circuit board?
I have removed the rubber membrane and circuit board because the buttons stopped working. Now I'd like to know how to properly clean the circuit board before reinstalling it?
Tammu Gray use some high grade (95%+) isopropyl alcohol. Use a brush (soft tooth brush works perfectly) to clean the board with that. Isopropyl alcohol in that concentration will evaporate quickly without leaving any residue and does not need to wait long for the board to be dry. Check this guide Repairing iPhone Liquid Damage step 30. Even so this is for a mobile phone, same principal applies. Of course the best way to clean it woiuld be with an ultrasonic cleaner