Close Door warning light on Kitchen Aid range

The Close Door warning light light appears when we try to use any of the convection oven settings (Bake, Broil, Roast) or when we try to use Broil under normal operation. As a result the oven will not reach temperature. The Bake setting does function properly and no warning light is displayed. I have removed the door and reset it it but this has not solved the problem. The door appears to be closed. I cannot find a door sensor. Any suggestions would be appreciated.