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First begin by opening your old remote. Take the circuit board out of it. Place the circuit board inside the button pad. Then put the button pad inside the new replacement case. Remove the battery from your old shell. The battery contact is the thing most people forget to move and then the remote doesn't work so don't forget to move the battery contact to the new shell before you put the battery in it. The battery contact should be fixed in it's holder exactly as it was positioned in your old shell. Close up the new housing around your old internals and you are done. Remote repaired!