Pioneer Mini Split Error Codes List with Causes and Fixes

By | November 1, 2023

Pioneer Mini Split Error Code List with Causes and Fixes

If you have a Pioneer mini split that is giving an error code, the list below gives the error meaning.

The Pioneer mini split error code list will give general information on what problem the unit is having.

Also below are common causes and fixes when a Pioneer mini split has an error.

General Pioneer Mini Split Error Codes List

Pioneer Mini Split Error Codes List and Meanings

  • E0: Indoor unit EEPROM parameter error
  • E1: Indoor/Outdoor units communication error
  • E2: Zero-crossing signal detection error
  • E3: Indoor fan Speed has been out of control
  • E4: Indoor room temperature sensor T1 open circuit or short circuit
  • E5: Evaporator coil temperature sensor T2 open circuit or short circuit
  • EC: Refrigerant leakage detection
  • F0: Current overload protection
  • F1: Outdoor ambient temperature sensor T4 open circuit or short circuit
  • F2: Condenser coil temperature sensor T3 open circuit or short circuit
  • F3: Compressor discharge temperature sensor TP open circuit or short circuit
  • F4: Outdoor unit EEPROM parameter error
  • F5: Outdoor fan speed has been out of control
  • P0: IPM malfunction or IGBT over strong current protection
  • P1: Over voltage or over low voltage protection
  • P2: High temperature protection of IPM module or compressor top
  • P3: Outdoor ambient temperature too low
  • P4: Inverter compressor drive error
  • P5: Indoor units mode conflict (multi-zone only)
  • P6: Low pressure protection (Only for 36K)

Pioneer Diamante Series Mini Split Error Codes List

  • EH 00 : Indoor unit EEPROM error
  • EH 0A : Indoor unit EEPROM parameter error
  • EL 01 : Communication error between indoor unit and outdoor units
  • EH 03 : Indoor fan speed error (DC motor)
  • EH 60 : Indoor room temperature sensor error (T1)
  • EH 61 : Indoor coil temperature sensor error (T2)
  • EL 0C : Refrigerant leakage detection (Cooling mode only)
  • PC 08 : Outdoor current overload protection
  • EC 53 : Outdoor ambient temperature sensor error (T4)
  • EC 52 : Outdoor coil temperature sensor error (T3)
  • EC 54 : Compressor discharge temperature sensor error (T5)
  • EC 51 : Outdoor unit EEPROM error
  • EC 07 : Outdoor unit fan speed error (DC fan motor)
  • PC 00 : Inverter module IPM error
  • PC 01 : High or Low voltage protection
  • PC 03 : High-Pressure or Low-Pressure Protection
  • PC 0L : Outdoor low ambient temperature protection
  • PC 04 : Compressor drive error
  • EH 0b : Communication error between main control board and display board

Pioneer Quantum Series Mini Split Error Codes List

  • E2 : IDU Coil temperature sensor failure.
  • E3 : ODU Coil temperature sensor failure. (OPT) ODU coil sensor and ODU PCB
  • E4 : AC Cooling system abnormal
  • E5 : IDU/ODU mismatched failure
  • E6 : IDU PG Fan motor / DC fan motor works abnormal(IDU failure)
  • E7 : ODU Ambient Temperature sensor failure ODU ambient sensor and ODU PCB.
  • E8 : ODU Discharge Temperature sensor failure. ODU discharge sensor and ODU PCB.
  • E9 : IPM/Compressor driving control abnormal. ODU PCB , compressor, etc.
  • EA : ODU Current Test circuit failure ODU PCB broken?
  • Eb : The Communication abnormal of Main PCB and Display board
  • EE : ODU EEPROM failure.
  • EF : ODU DC fan motor failure.
  • EU : ODU Voltage test circuit abnormal.
  • P0 : IPM module protection. ODU PCB
  • P1 : Over/under voltage protection.
  • P2 : Over current protection.
  • P4 : ODU Discharge pipe Over temperature protection.
  • P5 : Sub-cooling protection on Cooling mode.
  • P6 : Overheating protection on Cooling mode.
  • P7 : Overheating protection on Heating mode.
  • P8 : Outdoor Over temperature/Under temperature protection.
  • P9 : Compressor driving protection (Load abnormal).
  • PA : Multi-split conflict code (one indoor unit tries to heat while another tries to cool)
  • F0 : Infrared Customer feeling test sensor failure.
  • F1 : Electric Power test module failure.
  • F2 : Discharge temperature sensor failure. PROTECTION.
  • F3 : ODU coil temperature failure PROTECTION.
  • F4 : Cooling system gas flow abnormal PROTECTION.
  • F5 : PFC PROTECTION Please check the troubleshooting for detail.
  • F6 : The Compressor lack of phase / Anti-phase PROTECTION.
  • F7 : IPM Module temperature PROTECTION Please check the troubleshooting for detail.
  • F8 : 4-Way Value reversing abnormal.. Please check the troubleshooting for detail.
  • F9 : The module temperature test circuit failure. ODU PCB
  • FA : The compressor Phase-current test circuit failure.
  • Fb : Limiting/Reducing frequency for Over load protection on Cooling/Heating mode.
  • FC : Limiting/Reducing frequency for High power consumption protection.
  • FE : Limiting/Reducing frequency for Module current protection ( phase current of compressor).
  • FF : Limiting/Reducing frequency for Module temperature protection.
  • FH : Limiting/Reducing frequency for Compressor driving protection.
  • FP : Limiting/Reducing frequency for anti- condensation protection.
  • FU : Limiting/Reducing frequency for anti-frost protection.
  • Fj : Limiting/Reducing frequency for Discharge over temperature protection.
  • Fn : Limiting/Reducing frequency for ODU AC Current protection.
  • Fy : Gas leakage protection Please check the troubleshooting for detail.
  • Bf : TVOC sensor failure(IDU failure, optional)
  • bc : PM2.5 sensor failure(IDU failure, optional)
  • bj : Humidity sensor failure. (IDU failure)

Common Causes and Fixes for Pioneer Mini Split Units

  • Power Cycle the Unit
  • Power Cycle the Unit
    The first step for an error is to power off the unit and turn the breaker/disconnect off.

    Let the unit sit for 3-5 minutes with no power, then turn the breaker/disconnect back on and the power back on the unit.

    Often when an error occurs, it simply needs to be power cycled to clear.

    If the error comes back, then more troubleshooting will need to be done.

  • Bad Communication Wire or Connection
  • Bad Communication Wire or Connection
    While a component may have failed on a mini split system, many errors are caused by bad connections.

    This is mainly with the communication lines that run between the inside and outside units.

    The wires will be labeled inside the front panel on the inside unit and next to the power on the outside unit.
    Bad Communication Wire or Connection 2
    Check all the connections on the communication wires and check for any breaks often can solve issues.

    An HVAC technician will use multi meter to check for continuity on each line, making sure there are no opens or shorts.

  • Refrigerant Low
  • Refrigerant Low
    If there is a leak, the refrigerant will become low, and the unit will stop working.

    Often when the refrigerant is low, the inside condenser will start to drip water.

    A common error for a Pioneer mini split with low refrigerant is an EC error code, but other codes can also display, or in some cases, none will display.

    If the system is low on refrigerant, the leak will need to be found, and refrigerant added back into the system.

    A common failure point for leaks is the flares where the copper line set is bolted together.

    The flares that come from the manufacturer notoriously cause issues and can leak sometimes.

  • Condensing Fan Motor
  • Condensing Fan Motor
    The condensing fan is the big fan on the outside unit which blows air away from the unit.

    If it fails and stops working, it will cause issues.

    Check around the fan that no debris has blown into the outside unit and has stopped the fan from turning.

    If debris stops the fan from spinning, it will cause an issue and need to be cleaned out.

    The motor may also have gone bad or have a wiring issue.

  • Computer Board Bad Connection or Failure
  • One of the computer boards may have malfunctioned.

    The connections between the boards can all be pushed in to see if any have become loose.

    The onboard computer chips EEPROM and others can also be pushed in to be sure they are connected well.

    The boards can also go bad and need to be replaced.

    A board can go bad from a power spike or a bad wiring connection.

If your Pioneer mini split is giving an error code, use the chart above to see what the problem is with the unit.

For example, if the unit is displaying an E0 error code, the unit is having a problem with the indoor unit EEPROM parameter.

Once the error is known, try a power reset to see if the error clears.

When doing a power reset, it is best to pull the disconnect or turn off the breaker and wait a few minutes.

The communication lines between the units are a common failure and should be checked for any bad connections.

Other common issues include low refrigerant, condensing fan motor, and computer board problems.

Have you had an issue with a code on your Pioneer mini split? Let us know your thoughts below.

Category: Mini split heating and cooling air conditioner heat pump systems

About Aaron H. Benetti

Aaron H. Benetti an HVAC technician who has worked in the field since 1991. He began his career as an HVAC installer and later began doing troubleshooting and repairs. Around 2010, he began to write books on HVAC topics, mainly tutorials and how-to information. Currently, Aaron works as an HVAC tech and also writes many articles and posts for websites as well as books and videos on HVAC topics.

25 thoughts on “Pioneer Mini Split Error Codes List with Causes and Fixes

  1. Doanvin

    there was a rainstorm the other day that drenched my outdoor unit. usually its good but since then i been getting the E0 error code. I power cycled the unit a few times and it keeps going back to the error….. can it be the board got wet somehow and fried?

  2. Scott Randall

    I have had problems with my Pioneer unit from day one the main problem is it keeps throwing a PC04 code especially when it’s real cold or real hot. And the lines on inside units freezing up and the inside units actually freezing and ice coming out of them. I’m on social security and can’t afford to pay a hvac company to come our and fix the problem

  3. Mohammed

    Had a faulty main breaker issue. Apparently the
    main house breaker was over heating. Noticed my normal fan used to speed up and returned to the normal speed. And my ac blower wheel was doing some crazy high speed cycles and returned to normal. Also when it spinning slow, I hear a kind of grating/ gargling noise.
    Change main breaker;
    However, condenser fan was spinning slow. Change stater capacitor and fan capacitor. But insider blower wheel was still doing same. When the ac puts on, the blower wheel normal. However, after something it goes back to some hard blowing cycles, Iand when its blowing slow I hear that grating/ gargling sound by the motor, and feels some vibrations from the blower motor side.
    Hope you can help me out.
    Thanks in advance

  4. Marty Henderson

    I had the P4 code on 2 units so far this year … and on only 2 year old units… the first unit I troubleshot had the compressor shorting to ground… I have not had time to check the second unit yet… but getting a replacement
    condenser even at half price doesn’t even begin to cover the hassle of having to do the job again…

  5. McKenna Finlinson

    I have the Diamante Ultra and my kid got ahold of the remote and now it flashes OA the entire time it’s on, it blows air but not on the mode we set it or the temperature. I’ve tried pushing all the same buttons my kid could’ve and I can’t find this code ANYWHERE in ANY of the mini split stuff. Someone please help 😫

    1. Don

      It’s probably best to reset the system, flip off the breaker to the unit, remove the batteries in the remote control, and then power it all back on.

  6. Al

    Just installed pioneer 12k Error code E0. Comm wires good, all checks out
    Bad board???


    i have a pioneer 9 k btu its been in for 3 years no issue now showing FY error code please help not on list

  8. David Pusateri

    I have a brand new unit and was charged this morning and my A/C guy and my electrician can’t figure out what is wrong? It gives a code not listed. EL-01 Not sure how to trouble shoot this. David

    1. John Rutherford Jr

      I have the same issue called and they say it is the circuit board in the outside unit they are sending a new one.

  9. Samson Whyte

    I’m getting an f4 error code on my 24,000 cassette. Do I need to change my main pcb board?

  10. Danielle Cawley

    Just put in split level, PC03 is immediately showing up but the outdoor temperature is 80 degrees. How do you fix this.

    1. Mathias Arrua

      Did you figure out the problem? The same thing happened to me but haven’t fixed it.

    2. Anderson Ariza

      I have the same problem did you find out how to fix it.

  11. Alan Herrin

    I have a pioneer minisplit i have a code of P0 what should i do.

    1. Dee Rodriguez

      I just had the same error code. Unit works on AC but when on heat mode it doesn’t blow hot air.

  12. Gary Charles

    I put in a pioneer mini split after running it for 8 months I am getting a fp error code I can’t find that one listed

  13. John Tesvich

    I get an error code that shows “CP” as soon as the unit is turned on with the remote control.

    The error code “CP” is not covered in the list of error codes

  14. Brady Bennett

    I’m getting an F2 error code. The chart above says this is the condenser coil temp sensor. I had an HVAC guy look at it and his comment was that I should replace all of the sensors. I asked him to order them and never heard from him again. Followup calls resulted in no call back. I have been unable to locate sensors online. My unit is a WYS024G-19. Thoughts? Thanks.

  15. Fernando Galindo

    I keep getting a P4 error on my Pioneer mini Split. I’ve already topped off the R410A, replaced the outdoor PCB and capacitor. What else can I do besides ordering an $80 part (not including the $200+ shipping).

    1. Daniel Lewis

      Did you figure out your p4 code? I am getting the same. Just replaced an ipm board and it worked for about 8 hours. Now back to p4 code

      1. Shane

        Anyone figure out the P4 code? I’m getting the same thing over here.

        1. David Sidwell

          Me too. I got the P4 code, and hvac guy came and said the board needed replacement. I did that, and then it worked, but now the P4 error again.

  16. Jeremy Wheeler

    I have no error on the unit but sometimes the app says Evaporator temperature frequency limit abnormal any help would be appreciated. I can’t get anyone knows what it is.


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