Have a 14 years old Siemens dishwasher SE65M350EU - which I repaired twice over the last couple of weeks.
INSUFFICIENT FILLING WITH WATER
First problem was insufficient filling of water in the start of the cycle. I could hear that water did enter the machine, but level was very low inside the machine. Because of the low water levels, the rotor arms did not turn and the pump sounded like it needed liquid. I had to manually add 2 liter extra water for each cleaning phase (Pre-rinse, hot cleaning, final flush) for the dishwasher to work. Also an error “1 min” often appeared in the display - here the drain pump continued to run as the machine tried to empty.
I reasoned that the water inlet valve was just fine as water could enter to some degree. I pulled out the washing machine and unscrewed two screws (arrow F+G) on the front /left side, and easily took of the left metal cover plate – now I could see all the plastic water channels, tank and valves etc. I tried to find out how all this automation played out. It appeared that the machine starts by filling approx. 2 L in the 1-2 cm thick plastic tank (40x50 cm) on the side which is most of the photo. While filling this transparent tank, the liquid also flows into the machine through the inlet hose (Arrow E) – but if the inlet system (C+D+E) is blocked by dirt, the machine thinks it is full of water, and steps into the cleaning phase (No more filling of water).
By taking apart different parts, I found out the issue was dirt in the fill/overflow mechanism (photo arrow C+D) and dirt in the inlet hose (photo arrow E). I cleaned the dirt out using a bottle brush and a tooth brush and reassembled. Thereafter the water flow into the machine worked just fine.
INSUFFICIELT DRAINING
Second problem was draining which happened very slowly, and 1-2 liter of water could be seen inside after the machine had stopped draining – even resetting and re-draining did not work out. Drain pump seemed to work and hose was fine and clear. I again pulled out the machine and took of the left metal side plate. I found out that a lot of dirt was inside the two drain hoses (Photo arrow A+B). After cleaning of these hoses using the bottle brush, flow was very high and the machine would drain fast in ½-1 minute.