Mitsubishi Electric klima error codes
Codes
- A0Error codeerror> Abnormal points and detection method Address duplicate definition This error is displayed when transmission from the units of same address is detected. Note: The address and attribute displayed at remote controller indicate the controller that detected abnormality.
- A2Error codeHard ware error of transmission processor Transmission processor intended to transmit “0”, but “1” appeared on transmission wire. Note) The address and attribute display at remote controller indicate the controller that detected abnormality.
- A3Error codeBUS BUSY 1. Overtime error by signal collision damage Abnormal if transmitting signal is not possible for 8-10 minutes continuously because of collision of transmission. 2. Data could not reach transmission wire for 8-10 minutes continuously because of noise or etc. Note) The address and attribute displayed at remote controller indicate the controller that detected abnormality.
- A6Error codeCommunication error with communication processor Defective communication between unit processor and transmission processor Note: The address and attribute display at remote controller indicate the controller that detected abnormality.
- A7Error codeNO ACK signal 1. Transmitting side controller detects abnormal if a message was transmitted but there is no reply (ACK) that a message was received. Transmitting side detects abnormality every 30 seconds, 6 times continuously. Note) The address and attribute displayed at remote controller indicate the controller that did not reply (ACK). 2. If displayed address or attribute is outdoor unit, indoor unit detects abnormality when indoor unit transmits signal to outdoor unit and there was no reply ( | 4. If displayed address or attribute is remote controller, indoor unit detects abnormality when indoor unit transmits signal to remote controller and there was no reply (ACK). 5. If displayed address or attribute is FRESH MASTER, indoor unit detects abnormality when indoor unit transmits signal to FRESH MASTER and there was no reply (ACK). 6. If displayed address or attribute is LOSSNAY, indoor unit detects abnormality when indoor unit transmits signal to LOSSNAY and there was no reply (ACK). 7.
- A8Error code9-5. TROUBLESHOOTING Phenomena 1. Remote controller work. 2. “PLEASE WAIT” on the remote 3. When pressing operation switch, display is appeared turned off soon.: M-NET NO RESPONSE 1 Transmitting Abnormal if a message was transmitted repeated noise and and there were reply (ACK) that message 2 Extinction was received, but response command voltage does not return. Transmitting side detects by over-range abnormality every 30 seconds, 6 times wire. continuously. • Maximum Note) The address and attribute displayed • Remote at remote controller indicate the 3 Extinction controller that did not reply (ACK). voltage by type-unmatched sion wire. Type.... With shi
- E0Error code(6831, 6834): Remote controller transmission error (E0)/signal receiving error (E4) Abnormal if main or sub remote con- (1) troller cannot receive any transmission normally from indoor unit of refrigerant address “0” for 3 minutes. (Error code: E0) Abnormal if sub-remote controller could (2) not receive for any signal for 2 minutes. (Error code: E0) Abnormal if indoor controller board (1) cannot receive any data normally from remote controller board or from other indoor controller boards for 3 minutes. (Error
- E1Error coderemote controller board or from other indoor controller board for 3 minutes.
- E2Error codeAbnormal if the clock function of remote 2 controller cannot be normally operated. (Error code: E2) BY INFERIOR PHENOMENA Factor board • When LED1 on indoor controller Power supply of 220~240V 1 unit. Defective outdoor controller 2 Power supply of 220~240V 3 unit. Defective indoor controller 4 • When LED1 on indoor controller Mis-setting of refrigerant 1 (There is no unit corresponding address “0”.) board • When LED1 on indoor controller Connection failure of indoor/outdoor wire • When LED1 is l
- E3Error code(6832, 6833): Abnormal if the clock function of remote (2) controller cannot be normally operated. (Error code: E2) Remote controller transmission error (E3)/ signal receiving error (E5) Abnormal if remote controller could not (1) find blank of transmission path for 6 seconds and could not transmit. (Error code: E3) Remote controller receives and transmits (2) data simultaneously for comparison. If different data is detected 30 times in a row, it is judged to be an error. (Error code: E3) Abnormal if indoor c
- E4Error code(6831, 6834): Remote controller transmission error (E0)/signal receiving error (E4) Abnormal if main or sub remote con- (1) troller cannot receive any transmission normally from indoor unit of refrigerant address “0” for 3 minutes. (Error code: E0) Abnormal if sub-remote controller could (2) not receive for any signal for 2 minutes. (Error code: E0) Abnormal if indoor controller board (1) cannot receive any data normally from remote controller board or from other indoor controller boards for 3 minutes. (Error
- E5Error code(6832, 6833): Abnormal if the clock function of remote (2) controller cannot be normally operated. (Error code: E2) Remote controller transmission error (E3)/ signal receiving error (E5) Abnormal if remote controller could not (1) find blank of transmission path for 6 seconds and could not transmit. (Error code: E3) Remote controller receives and transmits (2) data simultaneously for comparison. If different data is detected 30 times in a row, it is judged to be an error. (Error code: E3) Abnormal if indoor c
- E6Error codeIndoor/outdoor unit communication error (Signal receiving error) Abnormal if indoor controller board could not receive any signal normally for 6 minutes after turning the power on. Abnormal if indoor controller board could not receive any signal normally for 3 minutes. Consider the unit as abnormal under the following condition When 2 or more indoor units are connected to an outdoor unit, indoor controller board could not receive a signal for 3 minutes from outdoor controller circuit board, a si
- E7Error codeIndoor/outdoor unit communication error (Transmitting error) Abnormal if “1” receiving is detected 30 times continuously though indoor controller board has transmitted “0”.
- E8Error codeIndoor/outdoor unit communication error (Signal receiving error) (Outdoor unit) (1) Abnormal if outdoor controller circuit board could not receive anything normally for 3 minutes.
- E9Error codeIndoor/outdoor unit communication error (Transmitting error) (Outdoor unit) • Abnormal if “0” receiving is detected 30 times continuously though outdoor controller circuit board has transmitted “1”. • Abnormal if outdoor controller circuit board could not find blank of transmission path for 3 minutes. Non defined error code
- EAError codeIndoor/outdoor unit connector miswiring, excessive number of units 1. Abnormal if the number cannot be checked automatically due to miswiring of indoor/outdoor unit connecting wire and etc. after power is turned on for 4 minutes. 2. Abnormal if outdoor controller circuit board recognizes excessive number of indoor units.
- EBError codeAbnormal if the indoor unit number cannot be set within 4 minutes after power on because of miswiring (converse wiring or disconnection) of indoor/outdoor unit connecting wire.
- ECError codeof the indoor/outdoor unit connecting wire. Startup time over The unit cannot finish Startup process within 4 minutes after power on.
- EDError codeSerial communication error 1. Abnormal if serial communication between outdoor controller circuit board and outdoor power circuit board is defective. 2. Abnormal if communication between outdoor controller circuit board and M-NET board is not available.
- EEError codeAbnormal if a connection of indoor unit and outdoor unit which uses different refrigerant is detected.
- EFError code(6607 6608): Non defined error code This code is displayed when non defined error code is received.
- F3Error code— 63L connector open Abnormal if 63L connector circuit is open for 3 minutes continuously after power supply. 63L: Low-pressure switch <A42N only>
- F5Error code— 63H connector open Abnormal if 63H connector circuit is open for 3 minutes continuously after power supply. 63H: High-pressure switch
- F9Error code2 connector open Abnormal if both 63H and 63L connector circuits are open for 3 minutes continuously after power supply. 63H: High-pressure switch 63L: Low-pressure switch <A42N only>
- FBError codeIndoor controller board Abnormal if data cannot be read normally from the nonvolatile memory of the indoor controller board. Remote controller control board 1 Abnormal if data cannot be read normally from the nonvolatile memory of the remote controller control board. (Error code: E1) 2 Abnormal if the clock function of remote controller cannot be operated normally. (Error code: E2)
- FHError codeSpecifications are: Refrigerant leak sensor error Abnormal if refrigerant sensor cannot detect errors normally. subject to change without notice.
- FLError codeENGLISH: Refrigerant leakage Abnormal if refrigerant leakage detected by a refrigerant leak sensor. Remote controller control board
- FSError codefunction is For 10 mins after switched on.: freeze protection when THW1 detects 10 consecutive seconds a temp. ≤ 3ºC for 10 not be displayed if; disabled, water circulation pump1
- P1Error code© 2025 Mitsubishi: Room temperature thermistor (TH1) 1. The unit is in three-minute resume prevention mode if short/open of thermistor is detected. Abnormal if the unit does not reset normally after three minutes. (The unit returns to normal operation, if it has normally reset.) 2. Constantly detected during cooling, drying and heating operation Short: 90 ˚C [194 ˚F] or more Open: -40 ˚C [-40 ˚F] or less Electric US, Inc.
- P2Error codeSpecifications: Pipe temperature thermistor/Liquid (TH2) 1. The unit is in three-minute resume prevention mode if short/open of thermistor is detected. Abnormal if the unit does not reset normally after three minutes. (The unit returns to normal operation, if it has normally reset.) 2. Constantly detected during cooling, drying, and heating (except defrosting) operation.
- P4Error codeAbnormality of drain sensor (DS) Suspensive abnormality, if short/open of 1 thermistor is detected for 30 seconds continuously. (The unit returns to normal operation, if it has normally reset.) Detect the following condition. 3 • During cooling and drying operation. • In case that pipe <liquid> temperature - room temperature <-10deg (Except defrosting) • When pipe <liquid> temp
- P5Error codeDrain pump is abnormal if the condition above is detected during suspensive abnormality. Constantly detected during drain pump operation.
- P6Error code© 2025 Mitsubishi: Freezing/overheating protection is working 1. Freezing protection (Cooling mode) The unit is in six-minute resume prevention mode if pipe <liquid or condenser/evaporator> temperature stays under -15 ˚C [5 ˚F] for three minutes after the compressor started. Abnormal if it stays under -15 ˚C [5 ˚F] for three minutes again within 16 minutes after six-minute resume prevention mode. 2. Overheating protection (Heating mode) The units is in sixminute resume prevention mode if pipe <Liquid or condenser
- P8Error code9-3. TROUBLESHOOTING Phenomena 1. Remote controller work.: Note 3: It takes at least 27 minutes to detect abnormality. Note 4: It excludes the period of defrosting (Detection restarts when defrosting mode is over) Heating range : 37.4°F (3°C) ≤ (Condenser/ Evaporator temperature (T63HS)− room temperature(TH1)) OF PROBLEMS display does not 12 VDC is not supplied 12–15 VDC is supplied however, no display • “Please Wait” is • “Please Wait” is Factor is remained on At longest 2 minutes after “Please Wait” is displayed Communication error between troller and
- P9Error codemistor / Condenser-Evaporator (TH5) The unit is in three-minute resume pro1 tection mode if short/open of thermistor is detected. Abnormal if the unit does not get back to normal within three minutes. (The unit returns to normal operation, if it has normally reset.) Constantly detected during cooling, dry2 ing, and heating operation (except defrosting) Short: 90: or more Open: -40: or less
- PAError codeForced compressor stop (due to water leakage abnormality) The unit has a water leakage abnormality when the following conditions, a) and b), are satisfied while the abovementioned detection is performed. a) The intake temperature subtracted with liquid pipe temperature detects to be less than -10 [14 30 minutes. (When the drain sensor is detected to be NOT soaked in the water, the detection record of a) and b) will be cleared.) b) Drain float switch detects to be in the water for more than 15 mi
- PBError codeSpecifications: Fan motor error Abnormal if a) or b) is detected during fan motor operation. a) When the number of rotations is detected to be below the lower limit for 30 seconds. b) When the number of rotations is detected to be above the upper limit for 30 seconds. are subject to change without notice. Troubleshooting by inferior Phenomena Cause When LED 1 on indoor controller also off. 1. Power supply of rated voltage on indoor controller supplied to outdoor unit off. 2. Defective outdoor controller 3. Powe
- PLError code<M-NET communication Check code: Abnormal refrigerant circuit During Cooling, Dry, or Auto Cooling operation, the following conditions are regarded as failures when detected for 1 second. a) The compressor continues to run for 30 or more seconds. b) The liquid pipe temperature or the condenser/evaporator temperature is 167˚F [75°C] or more. These detected errors will not be cancelled until the power source is reset.
- U1Error codeHigh pressure (High pressure switch 63H operated) /High compressor temperature (Thermal protector TRS operated) Abnormal if the high pressure switch 63H (4.15 MPa, 602 psig) or thermal protector TRS (230˚F [110°C]) operated during compressor operation
- U2Error code(TH4:1102) (TH33:1132): High discharge temperature • Abnormal if TH4 exceeds 257°F (125°C) or 230°F (110°C) continuously for 5 minutes. Abnormal if TH4 exceeds 230°F (110°C) or more continuously for 30 seconds after 90 seconds have passed since the defrosting operation started. • Abnormal if discharge superheat (Heating: TH4−T63HS) exceeds 158°F (70°C) continuously for 10 minutes. TH4: Thermistor <Discharge> Note: High comp. surface temperature Abnormal if TH33 exceeds 257°F (125°C). In the case of high comp. surface t
- U3Error code
- U4Error code(PAC-SK52ST) (Refer to 9-10.) Heatsink thermistor(TH8) is in the power module. Thermistors Symbol TH3,TH32
- U5Error codeThermistors Symbol Name TH3 Thermistor <Outdoor Thermistor <Outdoor TH6 Thermistor <Outdoor> TH7 TH8 Thermistor <Heatsink> Temperature of heatsink Abnormal if heat sink thermistor(TH8) detects temperature indicated below. A12, 18, 42N··············84:, 183˚F A24, 30, 36N··············81:, 177˚F
- U6Error codePower module Check abnormality by driving power module in case overcurrent is detected. (UF or UP error condition)
- U7Error codeToo low superheat due to low discharge temperature Abnormal if discharge superheat is continuously detected less than or equal to 5˚F [−15˚C] for 3 minutes even though linear expansion valve has minimum open pulse after compressor starts operating for 10 minutes.
- U8Error codeOutdoor fan motor Abnormal if the rotational frequency of fan motor is not detected during DC fan motor operation. Fan motor rotational frequency is abnormal if; • 100 rpm or below detected continuously for 15 seconds at 68˚F [20°C] or more outside air temperature. • 50 rpm or below or 1500 rpm or more detected continuously for 1 minute. To find out the detail history (latest) Detailed Refer to "10-10. FUNCTION OF SWITCHES, codes Overvoltage error • Increase in DC bus voltage to: A12, 18N: 400 V
- U9Error code01 02 04 08 | PFC error (Overvoltage/ Detailed codes Undervoltage/Overcurrent) • PFC detected any of the followings a) Increase of DC bus voltage to 420V.
- UDError codeOverheat protection Abnormal if outdoor pipe thermistor (TH3), condensing temperature T63HS detects 70: or more during compressor operation.
- UEError codeduring compressor operation. TH3: Thermistor <Liquid> Abnormal pressure of 63HS Abnormal if 63HS detects 0.1 MPa or less. Detection is inoperative for 3 minutes after compressor starting and 3 minutes after and during defrosting. 63HS: High pressure sensor