Daikin Aircon J6 Error Code
Use this Daikin J6 error code guide to capture the fault correctly and see what should be checked before parts are quoted. Match the model first; same-looking codes can point to different rows.
What does Daikin J6 mean?
Daikin J6 is listed as faulty heat exchanger temperature sensor, malfunction of heat exchanger thermistor, and heat-exchanger deicer temperature sensor R11T malfunction at sub PCB connector X15A in mixed model-family source rows, including VRV IV+ REYQ / REMQ heat recovery, VRV 5-S RXYSA R32, VRV 5 Heat Recovery REMA / REYA R32, VRV 5 Heat Pump RYMA / RXYA R32, and ERA-AYF AHU / air curtain. The loaded row is source-backed by official diagnostic material. Do not collapse this code across model families; use the model, series, or system type to choose the right row. Confirm the exact model, series, or signal row before accepting a parts quote.
Choose the matching source row
The same visible code has more than one source-backed meaning. Match the model family, system type, or reporting unit before approving parts.
| Code | What it means | What to check first |
|---|---|---|
| EZi | Faulty heat exchanger temperature sensor | Match this row to the installed model or reporting unit, then use the source-specific checks below. |
| General RA self-diagnosis guide | Malfunction of heat exchanger thermistor | Match this row to the installed model or reporting unit, then use the source-specific checks below. |
| J6-01 - master / J6-02 - slave 1 / J6-03 - slave 2 | Heat-exchanger deicer temperature sensor R11T malfunction at sub PCB connector X15A | Check the connection on the PCB or actuator. Match the alternating J6-01 display to the master source row. |
| J6-08 - master / J6-09 - slave 1 / J6-10 - slave 2 | Upper heat-exchanger gas temperature sensor R8T malfunction at main PCB connector X29A | Check the connection on the PCB or actuator. Match the alternating J6-08 display to the master source row. |
| J6-11 - master / J6-12 - slave 1 / J6-13 - slave 2 | Lower heat-exchanger gas temperature sensor R9T malfunction at main PCB connector X29A | Check the connection on the PCB or actuator. Match the alternating J6-11 display to the master source row. |
| VRV 5-S R32 - J6 | Outdoor de-icing temperature sensor malfunction | Check the R4T coil liquid-temperature sensor connection at A1P connector X30A. |
| VRV 5 Heat Recovery R32 - J6 / VRV 5 Heat Pump R32 - J6 | Outdoor de-icing or gas heat-exchanger temperature sensor malfunction | Check the outdoor de-icer and gas heat-exchanger sensor connections at the main PCB. |
| ERA-AYF AHU / air curtain | Outdoor heat-exchanger deicer temperature-sensor malfunction (J6-01) | Match this row to the installed model or reporting unit, then use the source-specific checks below. |
- Code
- EZi
- What it means
- Faulty heat exchanger temperature sensor
- What to check first
- Match this row to the installed model or reporting unit, then use the source-specific checks below.
- Code
- General RA self-diagnosis guide
- What it means
- Malfunction of heat exchanger thermistor
- What to check first
- Match this row to the installed model or reporting unit, then use the source-specific checks below.
- Code
- J6-01 - master / J6-02 - slave 1 / J6-03 - slave 2
- What it means
- Heat-exchanger deicer temperature sensor R11T malfunction at sub PCB connector X15A
- What to check first
- Check the connection on the PCB or actuator. Match the alternating J6-01 display to the master source row.
- Code
- J6-08 - master / J6-09 - slave 1 / J6-10 - slave 2
- What it means
- Upper heat-exchanger gas temperature sensor R8T malfunction at main PCB connector X29A
- What to check first
- Check the connection on the PCB or actuator. Match the alternating J6-08 display to the master source row.
- Code
- J6-11 - master / J6-12 - slave 1 / J6-13 - slave 2
- What it means
- Lower heat-exchanger gas temperature sensor R9T malfunction at main PCB connector X29A
- What to check first
- Check the connection on the PCB or actuator. Match the alternating J6-11 display to the master source row.
- Code
- VRV 5-S R32 - J6
- What it means
- Outdoor de-icing temperature sensor malfunction
- What to check first
- Check the R4T coil liquid-temperature sensor connection at A1P connector X30A.
- Code
- VRV 5 Heat Recovery R32 - J6 / VRV 5 Heat Pump R32 - J6
- What it means
- Outdoor de-icing or gas heat-exchanger temperature sensor malfunction
- What to check first
- Check the outdoor de-icer and gas heat-exchanger sensor connections at the main PCB.
- Code
- ERA-AYF AHU / air curtain
- What it means
- Outdoor heat-exchanger deicer temperature-sensor malfunction (J6-01)
- What to check first
- Match this row to the installed model or reporting unit, then use the source-specific checks below.
What to do now
Use these steps before customer action, a sensor check, or PCB quote.
Treat it as a fault signal
If the matching model-family source row applies to J6, do not reset it; record the code and arrange diagnosis. Confirm the matching source row before taking action on another model family.
Match the J6 family before taking action
Capture the J6 display and model sticker first. For the matching model-family source row, record the main code, alternating subcode, reporting outdoor-unit role, and model sticker, then arrange qualified VRV diagnosis. The same code can mean something different in another model family, so confirm the model before taking another action. Do not treat a generic power-cycle as a manufacturer reset procedure.
Send these to us
J6 error code, a clear display photo, Daikin indoor and outdoor model stickers, the selected family/source row, the controller or unit that reported the code, affected rooms and observed symptoms, and result of the matching manufacturer-listed customer action, if any
Source-specific guidance
These diagnostic-reference notes help match the code to the exact model. Electrical, refrigerant, wiring, resistance, and component checks are technician work, not DIY steps.
| Source detail | What it says |
|---|---|
| Diagnostic note | Stop the system if it smells burnt, leaks, or trips power; note the exact model and code before booking diagnosis. |
| Diagnostic note | Check the connection on the PCB or actuator. This overview row is for qualified VRV diagnosis; do not open panels, alter field wiring, handle refrigerant, or change commissioning settings. |
| Diagnostic note | Check the R4T coil liquid-temperature sensor connection at A1P connector X30A. |
| Singapore / model note | This row is taken from the selected Daikin operation manual's remote-controller fault diagnosis table. |
| Singapore / model note | Official Daikin SM-TS3 self-diagnosis row. Manual causes: Defective thermistor connection; Defective heat exchanger thermistor; Defective outdoor unit PCB. |
| Singapore / model note | Official Daikin 4PEN561154-1C overview row for REYQ8~20 and REMQ5U7Y1B VRV IV+ heat-recovery systems. The guide refers technicians to the service manual for the complete code list and detailed troubleshooting. |
- Source detail
- Diagnostic note
- What it says
- Stop the system if it smells burnt, leaks, or trips power; note the exact model and code before booking diagnosis.
- Source detail
- Diagnostic note
- What it says
- Check the connection on the PCB or actuator. This overview row is for qualified VRV diagnosis; do not open panels, alter field wiring, handle refrigerant, or change commissioning settings.
- Source detail
- Diagnostic note
- What it says
- Check the R4T coil liquid-temperature sensor connection at A1P connector X30A.
- Source detail
- Singapore / model note
- What it says
- This row is taken from the selected Daikin operation manual's remote-controller fault diagnosis table.
- Source detail
- Singapore / model note
- What it says
- Official Daikin SM-TS3 self-diagnosis row. Manual causes: Defective thermistor connection; Defective heat exchanger thermistor; Defective outdoor unit PCB.
- Source detail
- Singapore / model note
- What it says
- Official Daikin 4PEN561154-1C overview row for REYQ8~20 and REMQ5U7Y1B VRV IV+ heat-recovery systems. The guide refers technicians to the service manual for the complete code list and detailed troubleshooting.
What to check before repair
Choose the matching source-family row first, then use only that row's diagnostic branch and customer-action boundary.
| You can check | Technician should confirm |
|---|---|
| Before taking any action on J6, take a clear display photo. | Match J6 to one source-family decoder row before choosing a diagnostic branch. |
| Capture the Daikin model sticker and identify which controller or unit reported the code. | EZi: use the matching service procedure to test only the components and conditions named by faulty heat exchanger temperature sensor; require measured evidence before quoting parts. |
| If the matching model-family source row applies to your unit, record the main code, alternating subcode, reporting outdoor-unit role, and model sticker, then arrange qualified VRV diagnosis. Confirm the exact model family before taking a different customer action. | General RA self-diagnosis guide: use the matching service procedure to test only the components and conditions named by malfunction of heat exchanger thermistor; require measured evidence before quoting parts. |
| VRV IV+ REYQ / REMQ heat recovery: use the matching service procedure to test only the components and conditions named by heat-exchanger deicer temperature sensor R11T malfunction at sub PCB connector X15A; require measured evidence before quoting parts. | |
| VRV IV+ REYQ / REMQ heat recovery: use the matching service procedure to test only the components and conditions named by upper heat-exchanger gas temperature sensor R8T malfunction at main PCB connector X29A; require measured evidence before quoting parts. | |
| VRV IV+ REYQ / REMQ heat recovery: use the matching service procedure to test only the components and conditions named by lower heat-exchanger gas temperature sensor R9T malfunction at main PCB connector X29A; require measured evidence before quoting parts. | |
| VRV 5-S RXYSA R32: use the matching service procedure to test only the components and conditions named by outdoor de-icing temperature sensor malfunction; require measured evidence before quoting parts. | |
| VRV 5 Heat Recovery REMA / REYA R32: use the matching service procedure to test only the components and conditions named by outdoor de-icing or gas heat-exchanger temperature sensor malfunction; require measured evidence before quoting parts. | |
| VRV 5 Heat Pump RYMA / RXYA R32: use the matching service procedure to test only the components and conditions named by outdoor de-icing or gas heat-exchanger temperature sensor malfunction; require measured evidence before quoting parts. | |
| ERA-AYF AHU / air curtain: use the matching service procedure to test only the components and conditions named by outdoor heat-exchanger deicer temperature-sensor malfunction (J6-01); require measured evidence before quoting parts. | |
| Do not transfer a sensor, drain, valve, fan, compressor, electrical, or reset procedure from one family row to the other. |
- You can check
- Before taking any action on J6, take a clear display photo.
- Technician should confirm
- Match J6 to one source-family decoder row before choosing a diagnostic branch.
- You can check
- Capture the Daikin model sticker and identify which controller or unit reported the code.
- Technician should confirm
- EZi: use the matching service procedure to test only the components and conditions named by faulty heat exchanger temperature sensor; require measured evidence before quoting parts.
- You can check
- If the matching model-family source row applies to your unit, record the main code, alternating subcode, reporting outdoor-unit role, and model sticker, then arrange qualified VRV diagnosis. Confirm the exact model family before taking a different customer action.
- Technician should confirm
- General RA self-diagnosis guide: use the matching service procedure to test only the components and conditions named by malfunction of heat exchanger thermistor; require measured evidence before quoting parts.
- You can check
- Technician should confirm
- VRV IV+ REYQ / REMQ heat recovery: use the matching service procedure to test only the components and conditions named by heat-exchanger deicer temperature sensor R11T malfunction at sub PCB connector X15A; require measured evidence before quoting parts.
- You can check
- Technician should confirm
- VRV IV+ REYQ / REMQ heat recovery: use the matching service procedure to test only the components and conditions named by upper heat-exchanger gas temperature sensor R8T malfunction at main PCB connector X29A; require measured evidence before quoting parts.
- You can check
- Technician should confirm
- VRV IV+ REYQ / REMQ heat recovery: use the matching service procedure to test only the components and conditions named by lower heat-exchanger gas temperature sensor R9T malfunction at main PCB connector X29A; require measured evidence before quoting parts.
- You can check
- Technician should confirm
- VRV 5-S RXYSA R32: use the matching service procedure to test only the components and conditions named by outdoor de-icing temperature sensor malfunction; require measured evidence before quoting parts.
- You can check
- Technician should confirm
- VRV 5 Heat Recovery REMA / REYA R32: use the matching service procedure to test only the components and conditions named by outdoor de-icing or gas heat-exchanger temperature sensor malfunction; require measured evidence before quoting parts.
- You can check
- Technician should confirm
- VRV 5 Heat Pump RYMA / RXYA R32: use the matching service procedure to test only the components and conditions named by outdoor de-icing or gas heat-exchanger temperature sensor malfunction; require measured evidence before quoting parts.
- You can check
- Technician should confirm
- ERA-AYF AHU / air curtain: use the matching service procedure to test only the components and conditions named by outdoor heat-exchanger deicer temperature-sensor malfunction (J6-01); require measured evidence before quoting parts.
- You can check
- Technician should confirm
- Do not transfer a sensor, drain, valve, fan, compressor, electrical, or reset procedure from one family row to the other.
Family-specific repair decision
EZi: diagnose faulty heat exchanger temperature sensor on the matching Daikin system. Approve repair or replacement parts only after that branch has measured evidence for J6. General RA self-diagnosis guide: diagnose malfunction of heat exchanger thermistor on the matching Daikin system. Approve repair or replacement parts only after that branch has measured evidence for J6. VRV IV+ REYQ / REMQ heat recovery: diagnose heat-exchanger deicer temperature sensor R11T malfunction at sub PCB connector X15A on the matching Daikin system. Approve repair or replacement parts only after that branch has measured evidence for J6. VRV IV+ REYQ / REMQ heat recovery: diagnose upper heat-exchanger gas temperature sensor R8T malfunction at main PCB connector X29A on the matching Daikin system. Approve repair or replacement parts only after that branch has measured evidence for J6. VRV IV+ REYQ / REMQ heat recovery: diagnose lower heat-exchanger gas temperature sensor R9T malfunction at main PCB connector X29A on the matching Daikin system. Approve repair or replacement parts only after that branch has measured evidence for J6. VRV 5-S RXYSA R32: diagnose outdoor de-icing temperature sensor malfunction on the matching Daikin system. Approve repair or replacement parts only after that branch has measured evidence for J6. VRV 5 Heat Recovery REMA / REYA R32: diagnose outdoor de-icing or gas heat-exchanger temperature sensor malfunction on the matching Daikin system. Approve repair or replacement parts only after that branch has measured evidence for J6. VRV 5 Heat Pump RYMA / RXYA R32: diagnose outdoor de-icing or gas heat-exchanger temperature sensor malfunction on the matching Daikin system. Approve repair or replacement parts only after that branch has measured evidence for J6. ERA-AYF AHU / air curtain: diagnose outdoor heat-exchanger deicer temperature-sensor malfunction (J6-01) on the matching Daikin system. Approve repair or replacement parts only after that branch has measured evidence for J6.
The model sticker and reporting equipment must match one decoder row before diagnosis begins.
EZi: the quote must name the test result that proves this row's fault rather than borrowing a parts list from the other family.
General RA self-diagnosis guide: the quote must name the test result that proves this row's fault rather than borrowing a parts list from the other family.
VRV IV+ REYQ / REMQ heat recovery: the quote must name the test result that proves this row's fault rather than borrowing a parts list from the other family.
VRV IV+ REYQ / REMQ heat recovery: the quote must name the test result that proves this row's fault rather than borrowing a parts list from the other family.
VRV IV+ REYQ / REMQ heat recovery: the quote must name the test result that proves this row's fault rather than borrowing a parts list from the other family.
VRV 5-S RXYSA R32: the quote must name the test result that proves this row's fault rather than borrowing a parts list from the other family.
VRV 5 Heat Recovery REMA / REYA R32: the quote must name the test result that proves this row's fault rather than borrowing a parts list from the other family.
VRV 5 Heat Pump RYMA / RXYA R32: the quote must name the test result that proves this row's fault rather than borrowing a parts list from the other family.
ERA-AYF AHU / air curtain: the quote must name the test result that proves this row's fault rather than borrowing a parts list from the other family.
Compare repair cost, system age, parts availability, and overall condition only after the family-specific fault is proven.
Daikin J6 questions
What does the Daikin J6 error mean?
Can I fix a Daikin J6 error myself?
Is it safe to keep running the aircon with a J6 error?
What causes a Daikin J6 error?
Will a Daikin J6 error need a repair or a full replacement?
What should I send a technician about a Daikin J6 error?
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