The black plastic panels are behind the lower plastic trim below the door. Take that trim off, remove the black plastic panels and then get your hand in there with a sponge to mop up any water. Make sure power is switched off at wall plug before doing so. Another way is to tip dishwasher backward as far as possible & allow any water to come out of tray on to floor. Have some towels ready to catch the water.
Lincoln Appliance NZ
January 2015