How do I activate the Child Lock on the PDSH4816AF dishwasher?

To lock the dishwasher controls, press and release the AIR DRY pad for 3 seconds while the door is open. An indicator light on the lock graphic pad will illuminate when the controls are locked, and no new selections can be made until the lock is released. To unlock the controls, press the AIR DRY pad until the indicator light goes out. (Page 8)