Picture #5: Pry open the remote. This is the most difficult part. Take your time, it will open. The remote was going to the garbage anyway so breaking it wasn't so bad but it didn't break. Picture #6: Take another small screwdriver to pry it open. Picture #7: Here the opened remote. Picture #8: Here you have the battery connections (blue arrows), push button switches (yellow arrows). Don't touch the potentiometer (red circles) or you will change the remote frequency. Picture #9: Take a low power soldering iron and redo the battery connections. I think this one was the problem. Picture #10: Do the other battery connection.