I have gotten the dreaded high heat two leds flashing error on a Samsung dishwasher that is about 18 months old. The manufacturer suggested replacing the ECS sensor, the PCB and another part but instead of going with a very expensive repair by the local service tech, I decided to try the fix by myself since I am handy with electronics and have electrical experience.
The repair is pretty simple and straight forward:
1. Turn off power to the dishwasher from the main circuit breaker;
2. open the door and remove the two screws on the side holding the dishwasher in place (might have two gray caps);
3. pull the dishwasher out and flip it to the side.
4. remove the round plastic (black) cover from the bottom of the dishwasher (2 screws);
5. locate the sensor and unplug. Twist to remove. Make sure to save the o ring since the new sensor does not come with one.
6. Insert o ring on the new sensor, twist it in place and attached the connector;
7. assemble the back of the dishwasher, flip back and push in the slot then screw in the positioning screws and cover them with the caps;
8. turn power back on;
Voila!
I hope this helps. It should be a 45 minutes job.