Mitsubishi Error Code 4: Inverter Error
Warning: Your Mitsubishi HVAC system has an inverter error and needs professional attention.
How to Fix Mitsubishi Code 4
- Step 1: Turn off your HVAC system at the thermostat and the circuit breaker.
- Step 2: Check and replace your air filter if it's dirty.
- Step 3: Call a professional HVAC technician to diagnose and repair the issue.
How to Reset Mitsubishi Code 4
- 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.
What does 4 mean?
The Mitsubishi 4 error indicates a problem with your system's inverter, which controls the speed of the compressor. This error can be caused by a variety of issues, but it's important to note that it's not an immediate safety hazard. However, it's crucial to address this issue promptly to prevent further damage to your system.
Affected Models
Replacement Parts
| Part | OEM Number | Est. Cost |
|---|---|---|
| Inverter board | 505489-0000 | — |
Related Codes on Same Models
| Code | Description | Severity |
|---|---|---|
| 1 | Indoor/Outdoor Mismatch | Warning |
| 2 | Power Supply Phase Error | Warning |
| 3 | Communication Error | Warning |
| 5 | Outdoor Thermistor Open/Short | Warning |
| 6 | Indoor Freeze/Overheat | Warning |
| 7 | Outdoor Freeze/Overheat | Warning |
| E6 | Indoor/Outdoor Communication Error | Warning |
| E9 | Indoor/Outdoor Communication Fault | Warning |
| P1 | Intake Sensor Error | Warning |
| P2 | Indoor Pipe Thermistor Error | Warning |