Dishwasher does not heat water properly or shows HE error; dishes come out cold and wet.

Safety: Disconnect power before accessing internal wiring or heater components.

• Run a hot cycle: Start a normal or heavy cycle and open the door mid-wash (after 15–20 minutes) to feel the water. If it is cold, the heater is not operating.
• Inspect wiring: Remove the lower panel and check wiring harness connections to the heater and thermostat for burns or loose plugs.
• Test heater element: Use a multimeter to measure resistance across the Samsung heater terminals. An open circuit indicates a failed heater that must be replaced.
• Check high-limit thermostat: Test for continuity. If open and not resettable, replace it.
• Control board: If heater and sensors test good, the main PCB heater relay may be faulty and the board may need replacement.