How to Troubleshoot & Replace Whirlpool AP6009039 / WP3977678 Dryer Timer (4-Cycle)

Replaced timer 

I viewed the video on youtube from appliance parts pros. It looked like my problem. I ordered the piece. The piece matched up with the exception of a couple of extra wires that my timer on my dryer had, that we easily just matched up. First try at drying and it worked. Extremely simple and took only about 15 minutes. 

I ordered a timer and two solonoids for the gas valve. Problem solved dryer backin service.