E6

Indoor/outdoor unit communication error (Indoor unit receiving)

Mitsubishi Electric · PUZ-HA30/36NHA4 Outdoor Unit

What does E6 mean?

The indoor controller board fails to receive signals normally for 6 minutes after power-on, or 10 minutes during operation, or from the outdoor board in twin systems. This points to communication wire contact failure, short circuits, miswiring, noise, or defects in communication circuits or fan motor/rush current resistor. It severely impairs the indoor unit's ability to coordinate with the outdoor unit.

Additional Steps

Steps 1–2 are listed in Priority Fix.

  1. 3

    Detach the fan motor connector (CNF1, 2) and re-power; if the error clears, replace the fan motor. Otherwise, replace the outdoor controller circuit board.

  2. 4

    Use a tester to check resistor RS1 on the outdoor noise filter board; replace the board if it's open.

  3. 5

    If other indoor controller boards exist in a twin system, consider they might be defective.

Source: Mitsubishi Electric PUZ-HA30/36NHA4 Outdoor Unit
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