The F70 fault code appears when the anti-flood system is activated. It happens when water that accumulates in the bottom pan lifts a Styrofoam float, which, in turn, switches on the waterproof system. It means that water level in the bottom is above normal, and there is a problem.
Close the inlet valve and disconnect your dishwasher from the mains. Drain water from the bottom pan. To do so, prepare a tub, towels and rags (water may gush out suddenly). Tilt the washer forward until all water streams out.
Put the dishwasher on its side and remove the pan. Be very careful not to damage the ffloat! Locate screws and make pictures to avoid confusion when reassembling it. Check the drain hose for clogs and clean it, if necessary. Make sure there are no clogs in the household sewage. If these are all right, there may be a problem in the drain pump. If it proves to be faulty, replace it.
Also, water may fill the bottom pan when there is a leak in the inlet system.
Reassemble the dishwasher and run a short cycle to test it. Most likely, the issue will go. If it does not, address your local technical maintenance service.