What It Means
Communication signal transmission error between indoor and outdoor units.
Mitsubishi Electric All Systems
Mitsubishi Electric Error Code E6 – E7
Troubleshooting guide for the Mitsubishi Electric system fault E6 – E7.
ACLogics Fix Mitsubishi Electric code E6 – E7 See how ACLogics handles it → Fix E6 – E7 step-by-step
Possible Causes
- Indoor to outdoor unit communication failure.
- Inter-unit transmission line or wiring fault.
Not sure which one it is — or if it's none of these? Try ACLogics today.
Disclaimer: This information is for general reference. Error codes can vary by model and production year. Always refer to your machine's specific manual and the information printed on the unit itself.
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Full Diagnosis
Indoor/outdoor unit communication error.
All Recorded Causes
Verify Before Replacing Parts
- Confirm the exact Mitsubishi Electric model family and default context before acting on a generic code description.
- Confirm board LEDs, wiring polarity, and model compatibility before replacing control boards — this Mitsubishi Electric fault points at the most likely cause listed above.
- Check for intermittent communication faults caused by connectors, moisture, or damaged harnesses, and rule out the next candidate on the list.
- After the correction, run the system long enough to confirm the default fault does not return under normal load.
Not sure which system this Mitsubishi Electric code is on?
ACLogics has guided diagnostics for 73 Mitsubishi Electric fault codes and asks the right questions to narrow it down.
