Hi. your problem is actually a rather complicated one.
Timer and selector switches
The timer switch is usually the largest dial on the main control panel. It can be either a mechanical device much like a simple clock, or completely electronic with just a digital readout.
The timer runs the washing machine in a pre-determined pattern. It provides the electricity to all of the washing machine components at the correct time and for the correct length of time.
The Start switch is usually part of the timer knob. When you set the timer to the proper cycle, you either pull or push the timer knob to start the cycle.
The selector switches or knobs vary from machine to machine. Most washing machines have one or several switches or knobs on the control panel besides the Timer/Start switch. These let you adjust certain settings; for example, the water temperature, spin speed, timer cycle, and so on. Normally, the washing machine completes the cycle selected on the timer, regardless of how you set these switches and knobs.