First identify the upper or lower drawer and the level of the water. Fisher & Paykel’s DishDrawer guide says some water beneath the drain filter is normal. That is different from water standing across the drawer floor or escaping into the cabinet. DishDrawer user guide 591150E, maintenance section.
Photograph the water level and any code before clearing the display. Do not force a drawer that will not open normally.
A3 has a specific model boundary
Fisher & Paykel installation guide 431376A lists A3 as a failure to drain on its named DD24 families, including DD24DA and DD24DC. It points to a blocked or kinked drain hose or a blocked connection to the drainpipe. Check the hose and the drain connection before suspecting the pump. US/Canada DD24 installation guide, troubleshooting.
Keep the full model with the code. A code list for a different generation or a full-size dishwasher should not decide the repair.
What owner cleaning can cover
Guide 591150E starts filter care by disconnecting power and allowing all parts to cool; the filter plate can be hot. It describes removing and cleaning the drain filter and filter plate, then aligning and seating them correctly. The illustrations matter: the filter mesh and holder should not be squeezed or forced together in an improvised way.
Follow that guide only if it matches the installed drawer. If the filter is clean but A3 returns, stop treating the problem as ordinary maintenance. Leave concealed hoses and the drawer mechanism for service.
Water near a cord or outlet takes priority. Keep clear of wet electrical connections and stop using the appliance; do not keep running cycles to see how far the leak spreads.
For Fisher & Paykel service, contact ADRIUM with the affected drawer, model and photo. Our dishwasher repair page explains the service. The $99 diagnostic visit is credited toward an approved repair, and the repair scope is quoted after the drain path is checked.