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Home / Troubleshooting / Mitsubishi Mini Split Error Codes: How to Read Them and What to Check
Mitsubishi Mini Split Error Codes: How to Read Them and What to Check
Mitsubishi reports faults as two-character codes and as LED blink patterns. Here is how to retrieve a code and what the major families of codes point to.
In this article
- Retrieving the code
- What the code families mean
- The three things worth trying first
- Write the code down before you call
Codes vary between series and between indoor and outdoor units, so always confirm against the manual for your exact model number. What does not change is the method and the general meaning of each code family.
Retrieving the code
- Wall remote: most models display the code on the screen when a fault is active. Some require holding the check button for several seconds.
- Indoor unit LEDs: count the blink pattern on the operation and standby indicators. The pattern maps to a code in the manual.
- Outdoor board: service models show a code on a seven-segment display behind the service panel. Leave this to a technician; there is line voltage present.
What the code families mean
| Family | Points to | Homeowner action |
|---|---|---|
| Room and coil temperature sensor faults | A thermistor is open, shorted or out of range | Technician — inexpensive part |
| Indoor and outdoor communication faults | Wiring between units, or a control board | Check for obvious wiring damage, then call |
| Drain and float switch faults | Condensate not draining | Often fixable: clear the drain line |
| Fan motor faults | Motor, capacitor or obstruction | Check for obstruction, then call |
| Compressor and pressure faults | Refrigerant charge, blocked coil, overload | Clean coil and clear airflow, then call |
| Overcurrent and inverter faults | Power supply, inverter board | Technician only |
The three things worth trying first
- Clear the filters and the outdoor coil. A startling share of pressure and capacity faults are airflow problems wearing a costume.
- Check the condensate drain. Drain faults are the most common code homeowners can actually fix.
- Power cycle properly. Switch off at the breaker, wait five minutes, restore. If the same code returns immediately, it is a real fault, not a glitch.
Write the code down before you call
Give the technician the exact code, the model numbers of both units, whether the fault is constant or intermittent, and what the weather was doing when it appeared. That information routinely saves an hour of diagnostic labor.
Last checked August 2026. Prices are US ranges and vary by region — always confirm against written quotes.
