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Mitsubishi Electric Air Conditioner Error Codes
Find the code shown on your Mitsubishi Electric air conditioner and get a plain-English explanation with step-by-step fixes, easiest first. We cover 18 Mitsubishi Electric air conditioner codes, including Blinking OPERATION light, P1, P2 / P9, P4 / P5.
All 18 Mitsubishi Electric air conditioner codes
- Blinking OPERATION lightWall unit's indicator light is flashing
- P1Room air temperature sensor fault
- P2 / P9Indoor coil temperature sensor fault
- P4 / P5Drain sensor or drain pump problem
- PAShut down to prevent a water leak
- P6Freeze or overheat protection
- P8Pipe temperature error
- PbIndoor fan motor error
- FbIndoor control board error
- E0-E5Wall controller communication error
- E6 / E7 / E9Indoor and outdoor units aren't communicating
- U1 / UdHigh pressure or overheat protection
- U2Discharge temperature too high or low refrigerant
- U3 / U4Outdoor temperature sensor fault
- U6 / UP / UFCompressor overcurrent
- U8Outdoor fan stopped
- U9 / UHPower supply or current sensor problem
- PLRefrigerant circuit abnormal
About Mitsubishi Electric air conditioner error codes
Mitsubishi Electric is a Japanese manufacturer and one of the major names in ductless mini-split air conditioners and heat pumps. Its indoor units typically show faults as a blinking operation light or as a code read through the remote or wall controller, and codes differ between product series.
Of the 18 codes on this page, 0 usually have a simple fix you can do yourself, and 11 usually need a technician. Each guide tells you which is which, so you don't pay for a service call you don't need, and you don't attempt a repair that isn't safe.
Before you start
- Write down your model number. It's on a sticker, usually inside the door or lid, on the frame, or on the back or side panel. Parts and some code meanings depend on it.
- Try a reset. Unplug the air conditioner or switch off its breaker for 10 minutes. This clears many one-off glitches without tools.
- Clean or replace the air filter first. A dirty filter causes many airflow and freezing codes.
- Never open refrigerant lines or electrical panels. Those are jobs for a licensed HVAC technician.