Zanussi Electrolux DE 540 X Instruction Book page 7

If you are using dishwasher detergent that already contains
rinse aid, it is necessary to deactivate the inflow of rinse aid,
in order to avoid a double dosage.
To deactivate the inflow of rinse aid,
proceed as follows:
(The dishwasher must be switched off)
When the inflow of rinse aid has been deactivated, the
rinse aid indicator light on the control panel is
automatically deactivated.
1. Press the On/Off push button. The On/off indicator light
illuminates.
If other indicator lights are on, this means that a wash
programme has been selected. The programme must be
cancelled: press simultaneously the function push buttons
2 and 3 for about 2 seconds. All the indicator lights will turn
off (except for the On/Off indicator light).
2. Press simultaneously function push buttons 2 and 3, until
the indicator lights of the function push buttons 1, 2 and 3
start flashing.
3. Press the function push button 2, the indicator lights of
function push buttons 1 and 3 turn off while the indicator
light of the function push button 2 goes on flashing, at the
same time the indicator light END illuminates indicating that
the inflow of rinse aid is active.
4. To deactivate the inflow of rinse aid, press the function push
button 2 again, the indicator light END turns off, indicating
that the inflow of rinse aid has been deactivated.
5. To memorise the operation, switch off the dishwasher by
pressing the On/Off push button or wait about 60 seconds
after which the dishwasher will automatically return to
setting mode.
To activate the inflow of rinse aid follow the above instructions
until the indicator light END illuminates.
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