timer not working properly

Unplug dryer. First I removed timer knob( looks like one piece but it's actually two, the knob and the knob cap which will easily pry off). Then remove the three screws from top of control panel, the whole panel can then be tilted foward for timer removal. Timer can then be removed by sliding it to the left(when standing in front of dryer). Finally unplug connector from timer. Install in reverse order.