The Frigidaire Control Knob 131167601 is a replacement part for cycle settings. It is 1.75 inches in diameter and replaces 131167602. Safety precautions should be taken and the appliance should be disconnected before any repairs. Consult the owner's manual for instructions and part numbers.
A damaged timer knob that is unable to activate the timer can prevent the dryer from starting. Inspect the knob for cracks or wear and replace if necessary.