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Goodman Air Conditioner Error Codes

Updated · by Aurora Star Tech Inc.

52 Goodman 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.

Goodman Air Conditioner error codes list

CodeMeaningSeverity
01Low side fault or low pressure switch tripHigh
02High side fault or high pressure switch tripHigh
03Short cyclingMedium
04Locked rotorCritical
05Open circuit - compressor off over 4 hoursHigh
06Open start circuitCritical
07Open run circuitCritical
08No line voltageHigh
09Low 24 V control voltageMedium
b0Indoor blower not running when it should beHigh
b9Indoor airflow lower than requestedMedium
Comfort Alert 1Yellow ALERT 1 flash - long run timeMedium
Comfort Alert 2Yellow ALERT 2 flashes - system pressure tripHigh
Comfort Alert 3Yellow ALERT 3 flashes - short cyclingMedium
Comfort Alert 4Yellow ALERT 4 flashes - locked rotorCritical
Comfort Alert 5Yellow ALERT 5 flashes - open circuitHigh
Comfort Alert 6Yellow ALERT 6 flashes - open start circuitCritical
Comfort Alert 7Yellow ALERT 7 flashes - open run circuitCritical
Comfort Alert 9Yellow ALERT 9 flashes - low control voltageMedium
Comfort Alert TRIPRed TRIP LED - call present but compressor not runningHigh
Comfort Alert TRIP+ALERTTRIP and ALERT LEDs flashing together - control voltage too lowMedium
CoreSense 1Yellow 1 flash - long run time (low side)Medium
CoreSense 2Pressure trip - yellow 2 flashes (red 2 = lockout)High
CoreSense 3Short cycling / pressure switch cycling - yellow 3 (red 3 = lockout)Medium
CoreSense 4Locked rotor - yellow 4 (red 4 = lockout)Critical
CoreSense 5Moderate run trip - yellow 5 (red 5 = lockout)High
CoreSense 9Red 9 flashes - PROT output overcurrentHigh
CoreSense solid redSolid red TRIP - call present but compressor not runningHigh
d0No shared data on the networkHigh
d1Invalid shared data on the networkHigh
d2System mismatch - indoor unit cannot supply required airflowMedium
d3Configuration mismatch - shared data does not match hardwareHigh
d4Shared data from the loader rejectedHigh
E5Outdoor control low-voltage fuse openHigh
EEOutdoor control fault - compressor relay contacts weldedHigh
H8High line voltageHigh
L1Lockout - low pressure switch tripped 3 timesHigh
L2Lockout - high pressure switch tripped 3 timesHigh
L6Lockout - open start circuit detected 4 timesCritical
L7Lockout - open run circuit detected 4 timesCritical
L8Low line voltageHigh
P0Compressor protector openHigh
Yellow 1 flashLow side fault / low pressure trip / low pressure lockout (older ComfortNet board)High
Yellow 2 flashesHigh side fault / high pressure trip / high pressure lockout (older ComfortNet board)High
Yellow 3 flashesShort cycling (older ComfortNet board)Medium
Yellow 4 flashesLocked rotor (older ComfortNet board)Critical
Yellow 5 flashesOpen circuit (older ComfortNet board)High
Yellow 6 flashesOpen start circuit / lockout (older ComfortNet board)Critical
Yellow 7 flashesOpen run circuit / lockout (older ComfortNet board)Critical
Yellow 8 flashesLow or high line voltage (older ComfortNet board)High
Yellow 9 flashesLow 24 V control voltage (older ComfortNet board)Medium
Yellow ON + Red ONCompressor protector open (older ComfortNet board)High

Find codes by Goodman model

Goodman/Amana R-32 GLXS/ALXS

ALXS3BN**10AAALXS4BA**10AAALXS4NA**10AAALXS5BA**10AAGLXS3BN**10AAGLXS4BA**10AAGLXS4MA**10AAGLXS5BA**10AA

Goodman/Amana R-410A GSX/ASX/DSX (ANX/SSX/VSX)

ANX130181ANX130241ANX130301ANX130361ANX130421ANX130481ANX130601ANX130611ANX140181ANX140191ANX140241ANX140251ANX140301ANX140361ANX140371ANX140421ANX140431ANX140481ANX140601ASX180**1ABASX130181ASX130241ASX130301ASX130361ASX130421ASX130481ASX130601ASX130611ASX140181ASX140191ASX140241ASX140251ASX140301ASX140311ASX140361ASX140371ASX140421ASX140431ASX140481ASX140601ASX160181ASX160241ASX160301ASX160311ASX160361ASX160371ASX160421ASX160481ASX160601ASX160611ASXH5***10DSX160241DSX160361GSX16A181GSX16A241GSX16A301GSX16A361GSX16A421GSX16A481GSX16A601GSX16S181GSX16S241GSX16S301GSX16S361GSX16S421GSX16S481GSX110903GSX110904GSX111203GSX111204GSX130181GSX130241GSX130301GSX130361GSX130363GSX130371GSX130421GSX130481GSX130483GSX130484GSX130601GSX130603GSX130604GSX130611GSX140181GSX140191GSX140241GSX140251GSX140301GSX140311GSX140361GSX140371GSX140421GSX140431GSX140481GSX140601GSX160181GSX160241GSX160301GSX160311GSX160361GSX160371GSX160421GSX160481GSX160601GSX160611GSXH5***10SSX140181SSX140241SSX140301SSX140361SSX140421SSX140481SSX140601SSX160241SSX160301SSX160361SSX160421SSX160481SSX160591SSX160601VSX130181VSX130241VSX130301VSX130361VSX130371VSX130421VSX130481VSX130601VSX130611VSX140181VSX140191VSX140241VSX140251VSX140301VSX140311VSX140361VSX140371VSX140421VSX140431VSX140481VSX140601

Goodman/Amana ComfortNet ASXC/GSXC/DSXC

ASXC160241ASXC160361ASXC160481ASXC160601ASXC180241ASXC180361ASXC180481ASXC180601DSXC160241DSXC160361DSXC160481DSXC160601DSXC180361DSXC180481DSXC180601GSXC160241GSXC160361GSXC160481GSXC160601GSXC180241GSXC180361GSXC180481GSXC180601

Air Conditioner troubleshooting guides

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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