How do I add rinse aid and how do I know when it needs to be refilled?

The dishwasher will light up the Rinse Aid indicator on the control panel when the rinse aid is low and needs to be refilled. To refill, press on the latch of the rinse aid dispenser lid to open it, add liquid rinse aid until full (do not overfill), then close the lid until it clicks. Wipe up any spills with a damp cloth, and avoid spilling into the air vent hole. (Page 15)