The E20 error in the Bosch dishwasher indicates problems of the circulation pump. In addition, its parts or winding might be damaged.
Causes of error
As a rule, the circulation unit fails in extremely rare cases. So, before disassembling and checking the element, inspect the drainage system. The filter might be clogged. Also, the pump impeller might be blocked, too. For these reasons, the system shows the E20 code on the display.
What could have affected the failure of the circulation pump:
Voltage surges in the mains could lead to a break in the winding.
Water has got into electronic parts.
The heating element has burnt.
To fix the problem, you need to check everything consistently.
How to fix the damage yourself
First of all, try to reset the code. It might be a simple system crash. To do this, follow the instruction:
unplug the device from the mains;
wait 10-15 minutes;
start the dishwasher and look at the screen.
Do the icons light up again? Then start cleaning the filter. You have to:
Open the device door.
Remove the basket for the dishes.
Unscrew the drain filter, located in the pan.
Rinse it under the pressure of water or clean it with a brush.
Pull over and remove the cover.
A drain pump is located behind the filter.
Pump the water out of the hole with a sponge.
Remove the fixing screws.
Check the impeller for obstruction.
How to understand that the circulation pump does not work? During the dishwasher operation, you will not hear how the unit is buzzing. To check or replace the part, you need to disassemble the Bosch dishwasher:
Pull all the baskets out of the case.
Disconnect the machine from the mains and pull out the plug from the socket.
Turn the technique “on the back.”
Unscrew bolts or unfasten the latches of the bottom panel.
Carefully inspect the wiring for burning.
Remove the drain pump and the heating element. Check whether these parts are in order or not.
The diagnostics of the parts and winding of the block is carried out by the multimeter tester. To do this, the probes are applied to the contacts of the elements. Then, measure the resistance.