ErrorCodeDoctor
Daikin Air Conditioner J4 error code
The J4 error means your Daikin air conditioner detected a fault with the low pressure equivalent saturated temperature sensor system. Contact a qualified technician to inspect and replace the sensor.
Common causes
- Defective connection of thermistor
- Defective thermistor
- Defective outdoor unit PCB
How to fix it
-
1
Contact a qualified technician to inspect and replace the low pressure saturated temperature sensor
Related Daikin Air Conditioner error codes
A0
An external protection device connected to the indoor unit has been activated
A1
A fault was detected in the indoor unit PCB (control board)
A3
The drain level control system has detected an abnormality — drain may be clogged
A5
Freeze-up protection (cooling) or high pressure control (heating) has activated — check the air filter
J4 error — frequently asked questions
What does the J4 error mean on a Daikin air conditioner?
The low pressure equivalent saturated temperature sensor has a fault
What causes the J4 error?
The J4 error is usually caused by: Defective connection of thermistor; Defective thermistor; Defective outdoor unit PCB.
Can I fix the J4 error myself?
This is rated a hard fix — it often requires tools, parts, or experience, and may be safer left to a professional technician.
How much does it cost to fix the J4 error?
Fixing the J4 error on a Daikin air conditioner typically costs $80–$250, depending on parts and whether you do it yourself or hire a technician.
Is it safe to keep using my air conditioner with the J4 error?
We'd recommend addressing the J4 error before continuing to use the air conditioner, since hard-rated issues often involve a real fault rather than a minor glitch.