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Trane Air Conditioner Error Codes

Updated · by Aurora Star Tech Inc.

57 Trane Air Conditioner error codes and diagnostic codes, with causes and troubleshooting steps for each. Select a code, or find your model below.

Homeowner with a air conditioner problem? Call (647) 657-2977 or book a service call — licensed technicians across Vaughan and the GTA.

Trane Air Conditioner error codes list

CodeMeaningSeverity
2nd digit 1MOC fault (A1000AA board)High
2nd digit 2MOC communication fault (A1000AA board)High
2nd digit 3Compressor internal protection (IOL/OLP) (A1000AA board)High
2nd digit 4Compressor over-current protection (A1000AA board)High
2nd digit 5Outdoor fan over-current protection (A1000AA board)High
2nd digit 6High preheat IPM temperature (A1000AA board)High
2nd digit 7High coil temperature protection (A1000AA board)High
2nd digit 8High discharge temperature protection (A1000AA board)High
2nd digit 9High drive compressor IPM temperature (A1000AA board)High
2nd digit AOutdoor ambient sensor fault (A1000AA board)Medium
2nd digit bAOC jumper pin engaged (A1000AA board)Medium
2nd digit CCoil temperature sensor fault (A1000AA board)Medium
2nd digit dDischarge temperature sensor fault (A1000AA board)Medium
2nd digit EHigh drive PFC temperature protection (A1000AA board)High
2nd digit FHigh drive fan IPM temperature protection (A1000AA board)High
2nd digit PPressure protection (high or low) (A1000AA board)High
d5De-rate: drive AC input over-currentMedium
d6De-rate: high drive IPM temperatureMedium
d7De-rate: high drive PFC temperatureMedium
d8De-rate: high coil temperatureMedium
dCDe-rate: compressor over-currentMedium
ddDe-rate: high discharge temperatureMedium
dFDe-rate: outdoor fan over-currentMedium
E0Personality module errorHigh
E1Configuration errorHigh
E2AOC software / configuration mismatchHigh
F0AOC-MOC communication faultHigh
F1Compressor start-up faultHigh
F2Compressor over-currentHigh
F3Compressor control faultHigh
F4Outdoor fan control faultHigh
F5AC over-current faultHigh
F6Drive high temperature faultHigh
F7AC input voltage lowHigh
F8DC output voltage faultHigh
F9Drive (MOC) internal faultHigh
FAOutdoor ambient sensor faultMedium
FCCoil temperature sensor faultMedium
FdDischarge temperature sensor faultMedium
H5Hard lock: drive AC input over-currentCritical
H6Hard lock: high drive IPM temperatureCritical
H7Hard lock: high drive PFC temperatureCritical
H8Hard lock: high coil temperatureCritical
HCHard lock: compressor over-currentCritical
HdHard lock: high discharge temperatureCritical
HFHard lock: outdoor fan over-currentCritical
HHHard lock: high pressure (HPCO / DTC)Critical
HLHard lock: low pressure (LPCO)Critical
L5Lockout: drive AC input over-currentHigh
L6Lockout: high drive IPM temperatureHigh
L7Lockout: high drive PFC temperatureHigh
L8Lockout: high coil temperatureHigh
LCLockout: compressor over-currentHigh
LdLockout: high discharge temperatureHigh
LFLockout: outdoor fan over-currentHigh
LHLockout: high pressure (HPCO / DTC)High
LLLockout: low pressure (LPCO)High

Find codes by Trane model

5TTR7024A5TTR7036A5TTR7048A5TTR7060A

Air Conditioner troubleshooting guides

Trane Air Conditioner specs and setup data

Homeowner help: AC Running But Not Cooling: What to Check

General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.

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