The pump is blocked with foreign objects or the pump cover is not attached correctly.
Cleaning pump:
1. Set the programme selector to OFF. Pull out the mains plug. Attention: The pump may be blocked with glass fragments. There is risk of cutting yourself.
2. Remove the filters.
3. Remove the pump cover.
4. Remove all foreign objects.
5. Check whether pump impeller can be rotated freely.
6. Re-insert the pump cover including locking or screwing tight.
7. Also re-adjust the filters correctly and attach them if required.