I know in handsfree connector is working or not-for nokia 3110c/6300

click on images to enlarge picture

simple and easily pulled the plug handsfre know it works or not
What if the damage to his swith on the screen .. maybe ill come pic HF. can check at that part
and if the on-screen image appears HF HF but the device was not required to function instead of the switch means can be of corrosion from his hands-free connector / or devices are also already damaged HF