Mitsubishi Error Code E6: Indoor/Outdoor Communication Error
Warning: Your Mitsubishi HVAC system has encountered an indoor/outdoor communication error. It's safe to operate, but a professional repair is needed.
LED Blink Pattern
How to Fix Mitsubishi Code E6
- Check for any visible damage to the communication wire
- Ensure the outdoor unit's fan is running
- Contact a professional HVAC technician for repair
How to Reset Mitsubishi Code E6
- Turn off the unit using the remote control or wall controller.
- Turn off the circuit breaker for the outdoor and indoor units. Wait 60 seconds.
- Restore power at the breaker.
- Turn the unit on with the remote control. If the error returns, the fault needs professional diagnosis.
Resetting clears the code from the display but does not fix the underlying fault. If the code returns after reset, proceed to the diagnostic steps above.
What Does Mitsubishi Error Code E6 Mean?
The E6 error on your Mitsubishi HVAC system indicates a communication issue between the indoor and outdoor units. This could be due to a faulty communication wire, a problem with the control board, or an issue with the outdoor unit's fan. The system will continue to operate, but some features may be limited.
Common Causes
- Faulty communication wire
- Problem with the outdoor unit's control board
- Issue with the outdoor unit's fan
Diagnostic Steps
| If... | Check | Expected |
|---|---|---|
| Communication wire is damaged or disconnected | Inspect the wire for any visible damage or disconnection | Intact and connected wire |
| Outdoor unit's fan is not running | Measure the fan's resistance using a multimeter | Normal resistance (check manual for specific value) |
Applicable Mitsubishi Models
- City Multi (VRF)(electric)
- City Multi (Y)(electric)
- Diamond (PJ)(electric)
- Diamond Plus(electric)
- Diamond Series(electric)
- Ducted Systems(electric)
- M-Series(electric)
- MSZ(electric)
- MSZ Series(electric)
- MSZ-AP(electric)
- MSZ-AP Series(electric)
- MSZ-AP5 Series(electric)
- MSZ-AS(electric)
- MSZ-FD(electric)
- MSZ-FE(electric)
- MSZ-FS(electric)
- MSZ-FS/FD Series(electric)
- MSZ-FT(electric)
- MSZ-FY(electric)
- MSZ-GE(electric)
- MSZ-LV(electric)
- MUZ-FE Series(electric)
- P-Series(electric)
- PUMA(electric)
- PUMY(electric)
- Puff (P-Series)(electric)
Replacement Parts
| Part | OEM Number | Est. Cost | Where to Buy |
|---|---|---|---|
| Communication Wire | — | — | — |
| Outdoor Unit Control Board | 53005-3000 | — | Find Part |
Related Codes on Same Models
Other codes that affect the same Mitsubishi model families as E6.
| Code | Description | Severity |
|---|---|---|
| 1 | Indoor/Outdoor Mismatch | Warning |
| 2 | Power Supply Phase Error | Warning |
| 4 | Inverter Error | Warning |
| 7 | Outdoor Freeze/Overheat | Warning |
| E9 | Indoor/Outdoor Communication Fault | Warning |
| P2 | Indoor Pipe Thermistor Error | Warning |
| P4 | Drain Sensor Error | Warning |
| P6 | Coil Freeze/Overheat Protection | Warning |
| U2 | Low Voltage/Overcurrent | Warning |
| U3 | Discharge Thermistor Short/Open | Warning |