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Code 56 - Dual Temperature Switch

  1. Ensure water temperature was above 55°F (13°C) during Self-Test when code was observed.
  2. Check contacts of dual temperature switch (should be closed above 55°F/13°C). If resistance measures less than 5 ohms, go to step 3). If above 5 ohms, replace dual temperature switch.
  3. Measure resistance in wiring between MCU (pins 19 and 14) and dual temperature switch. If resistance is less than 5 ohms, replace MCU module. If greater than 5 ohms, repair wiring.
  4. Disconnect harness from mid temperature switch and measure resistance between wire leading to MCU pin 19 and ground. If resistance is less than 1000 ohms, repair wire leading to MCU pin 19. If resistance is greater than 1000 ohms, replace MCU.
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