Open the front cover of the left unit.
Raise the E1 plate, lower the lever D1, and then pull out the unit in the left drawer until it stops.
Pull up the lever D2 and clean the sensors.
Use a dry cloth to clean the plate.
Push down the lever D2.
Push the left drawer into the main unit until it stops, and then pull up the lever D1.
Close the E1 plate.
Close the front covers.