Hello everyone, The fingerprint sensor is married to the motherboard - replace the finger print sensor and you can't update to iOS 9. I have changed over hundreds of screens and haven't damaged 1 ribbon cable. I use a heat gun to soften the glue around the sensor and a knife to pick up the ribbon connector off the screen. Also the phone needs to be rebooted once if the fingerprint sensor has been disconnected and reconnected. If you do need to change the fingerprint sensor, keep it and place it back in to update otherwise "Error 53"