Goodman Error Code CoreSense 1: Yellow 1 flash – long run time (low side) (AC)
Goodman error code CoreSense 1 on a air conditioner means: Yellow 1 flash - long run time (low side). It is also called Goodman diagnostic code CoreSense 1.
Homeowner? What Goodman code CoreSense 1 means for you
Check, then call Your air conditioner is reporting: Yellow 1 flash - long run time (low side). This is often caused by something simple. Try the safe checks below; if the code returns, book a service call before it turns into a no-heat or no-hot-water emergency.
Safe things you can check yourself
- Check the thermostat: right mode (Heat or Cool), set a few degrees past room temperature, and fresh batteries if it uses them.
- Check both breakers and the outdoor disconnect box beside the outdoor unit; all should be ON.
- Look at the air filter. If it is grey and clogged, replace it; a blocked filter causes many shutdowns.
- Keep about 2 feet around the outdoor unit clear of leaves, grass and debris.
- If you see ice on the pipes or the indoor coil, turn the system off and run only the fan for a few hours, then call a technician.
- Try one reset: turn the power off for 30 seconds, then back on. If the code comes back, stop resetting and call a technician.
Call (647) 657-2977Book a service call
Licensed technicians serving Vaughan, Toronto and the GTA.
What does Goodman error code CoreSense 1 mean?
Compressor has run more than 18 hours straight, showing low capacity from a low-side problem. This code is disabled in heat pump heating mode.
Applies to: Copeland CoreSense 3-wire module: Amana/Deluxe R-410A ASX, ASZ, DSX, DSZ units and Amana R-32 ALXS / ALZS units
Common causes of Goodman code CoreSense 1
- Low charge
- Indoor blower not running (relay, capacitor, motor, wiring, indoor board, open thermostat wire)
- Frozen evaporator (low suction, low set point, blocked coil/filter/ducts)
A technician checks these and 3 other possible causes on site before replacing any part.
Goodman models that use code CoreSense 1
Show all 150 models
ALXS3BN**10AAALXS4BA**10AAALXS4NA**10AAALXS5BA**10AAANX130181ANX130241ANX130301ANX130361ANX130421ANX130481ANX130601ANX130611ANX140181ANX140191ANX140241ANX140251ANX140301ANX140361ANX140371ANX140421ANX140431ANX140481ANX140601ASX180**1ABASX130181ASX130241ASX130301ASX130361ASX130421ASX130481ASX130601ASX130611ASX140181ASX140191ASX140241ASX140251ASX140301ASX140311ASX140361ASX140371ASX140421ASX140431ASX140481ASX140601ASX160181ASX160241ASX160301ASX160311ASX160361ASX160371ASX160421ASX160481ASX160601ASX160611ASXH5***10DSX160241DSX160361GLXS3BN**10AAGLXS4BA**10AAGLXS4MA**10AAGLXS5BA**10AAGSX16A181GSX16A241GSX16A301GSX16A361GSX16A421GSX16A481GSX16A601GSX16S181GSX16S241GSX16S301GSX16S361GSX16S421GSX16S481GSX110903GSX110904GSX111203GSX111204GSX130181GSX130241GSX130301GSX130361GSX130363GSX130371GSX130421GSX130481GSX130483GSX130484GSX130601GSX130603GSX130604GSX130611GSX140181GSX140191GSX140241GSX140251GSX140301GSX140311GSX140361GSX140371GSX140421GSX140431GSX140481GSX140601GSX160181GSX160241GSX160301GSX160311GSX160361GSX160371GSX160421GSX160481GSX160601GSX160611GSXH5***10SSX140181SSX140241SSX140301SSX140361SSX140421SSX140481SSX140601SSX160241SSX160301SSX160361SSX160421SSX160481SSX160591SSX160601VSX130181VSX130241VSX130301VSX130361VSX130371VSX130421VSX130481VSX130601VSX130611VSX140181VSX140191VSX140241VSX140251VSX140301VSX140311VSX140361VSX140371VSX140421VSX140431VSX140481VSX140601
Other Goodman AC codes
All Goodman Air Conditioner error codes →
Goodman code CoreSense 1: homeowner questions
What does Goodman code CoreSense 1 mean?
Yellow 1 flash - long run time (low side). Compressor has run more than 18 hours straight, showing low capacity from a low-side problem. This code is disabled in heat pump heating mode.
Is it safe to keep using my air conditioner with code CoreSense 1?
It depends on the cause. This is often caused by something simple. Try the safe checks below; if the code returns, book a service call before it turns into a no-heat or no-hot-water emergency.
Can I reset Goodman code CoreSense 1 myself?
You can try one reset (power off for 30 seconds, then on). If Goodman code CoreSense 1 comes back, the cause is still there and a licensed technician should check it.
Who can fix Goodman code CoreSense 1 near me?
Aurora Star Tech Inc. repairs Goodman air conditioners in Vaughan, Toronto and across the GTA. Call (647) 657-2977 or book a service call online.
Homeowner help: AC Running But Not Cooling: What to Check
Troubleshooting guides
- Not cooling All brands · Air Conditioner
- No cooling - R-32 GLXS/ALXS condenser Goodman · Air Conditioner
Source: Goodman RS6200301 R-32 GLXS/ALXS/GLZS/ALZS service (07-2024), CoreSense Diagnostics Table p.21-22 and Quick Reference Table p.23; Goodman RS6200006r103 R-410A ASX/GSX/DSX/ASZ/GSZ/DSZ service (text export) (Goodman_R_410A_ASX_GSX_DSX_A_C_and_ASZ_GSZ_DSZ_HP_covers_GSX_GSZ_lines_GSXH5_GSZH5_service.txt section Diagnostics Table: Coresense Module / Table 1 Quick Reference). Written in our own words as a summary; always check the original manual.
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.