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.
- 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.
- 4
Use a tester to check resistor RS1 on the outdoor noise filter board; replace the board if it's open.
- 5
If other indoor controller boards exist in a twin system, consider they might be defective.