The picture below is about how to repair the Nokia 101 ringer buzzer problem, it can not make a sound, bad sounds .to make improvements please follow the instructions in the image above. try to check the red and blue lines on the image above. if the second line is normal then you try to change ringer ic like the picture below.
If there is any water damge or rust on mother board then clean it with electronic cleaner hot air for a few mint so that it can be dry.
check ringers point after opening the mobile.if ringers point is not working and its value is not right then replace it with new ringer.problem will be solved.if problem will not be solve then check ringers point on board.If there value is not right then check parts and components with there path from above diagram.If some path is missing then apply jumper.If any part and components is not working replace it with new one.