I have a whirlpool dyer model number LER5620KQ1. the light stays on when the door is closed and the dryer will not run. I have jiggled the door around and sometimes it will start.
Here are your parts
Replacement parts for WHIRLPOOL LER5620KQ1 | AppliancePartsPros.com
Here is the wiring diagram
http://www.servicematters.com/docs/wiring/Wiring%20Sheet%20-%208528187.pdf
Could be just the door switch actuator needs adjusting so the door closes the switch.
Just bend it, but be as gentle as you can you do not want to break it.
Could also be the switch is toast.