E33 is documented by Siemens as an excessive foam warning. Check the detergent dose and product before treating the interruption as an internal fault.
The same amount does not work for every load
The manufacturer documentation advises reducing detergent when the water is soft or the laundry is only lightly soiled. Check the concentration, the actual load, and any pre-treatment products. If you use automatic dosing, check its settings and avoid adding a manual dose at the same time unless the program requires it.
Foam can extend rinses or affect the spin result. Watch to see whether the machine follows a built-in correction routine and let it finish when there is no water loss.
After correcting the product and amount
Follow the cycle recovery steps in the E-Nr manual; there is no fixed time for E33 to disappear. Do not add vinegar, oil, or other remedies to neutralize the foam.
See how much detergent to use to prepare the next load. If the warning returns with the proper dose or is combined with a drainage problem, note those conditions and request service. The code does not confirm that a sensor is faulty.
Keep the detergent container and the amount used if the issue started after switching detergents.