Daikin aircon PCB repair in Singapore
A Daikin board code says which circuit reported the fault, not whether the board itself has failed. We test the indoor PCB, outdoor PCB and inverter or driver stage separately, explain what failed and quote after diagnosis.
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Signs your Daikin aircon needs a PCB check
These symptoms can involve a control board, but they can also come from wiring, a sensor or another part connected to the board.
The unit has power but will not start
Lights or the controller may still respond while the indoor unit, outdoor unit or both refuse to run normally.One room or the whole system stops responding
The pattern across rooms helps separate an indoor-board problem from an outdoor or shared communication fault.A communication or board-related error appears
A Daikin code, blinking light or repeated restart gives us a useful starting point, but it still needs electrical testing.
Examples of Daikin systems we check
iSmile CTKS / CTKB and MKS multi-split systems
iSmileEco CTKM / CTKP and EZi CTKC systems
iSmart ENVi FTKM single-split systems; SkyAir or VRV scope confirmed from the exact model
Model not listed
Send photos of the indoor and outdoor model labels, plus the error code or a short video of the symptom.
A board-related code does not always mean a failed PCB
Before ordering model-specific electronics, we check three problems that can make a healthy board appear faulty.
Power or wiring fault
Loose terminals, a damaged interconnect or unstable supply can produce board and communication errors.Sensor or connected load
A shorted thermistor, motor or valve can pull down a healthy board or make its input look incorrect.Inverter power stage
On inverter systems, the main control PCB and the IPM or driver circuit are tested as separate failure points.
We check the power supply, communication wiring, sensors, connected loads, indoor and outdoor boards, and inverter drive where fitted. How a job runs, from first message to booking.
What is different on Daikin systems
Daikin inverter efficiency depends on more control electronics. On systems past about eight years, the indoor board, outdoor board and inverter power stage must be separated before a replacement is approved.
Daikin error codes related to PCB problems
Open the group that matches where the code appeared on your unit.
Indoor unit or controller9 guides
- A1Indoor PCB defectiveness; Malfunction of indoor unit PCB
- A7Indoor swing-flap motor malfunction
- A8Power supply voltage abnormality
- C1Failure of transmission between indoor PCB and sub PCB; Transmission error involving the indoor unit PCB, fan PCB, or auto-grille control PCB
- U4Failure of transmission between indoor and outdoor unit; Transmission fault between indoor and outdoor unit
- U5Transmission fault between indoor unit and remote controller; Transmission error between the remote controller and indoor unit
- U8Transmission fault between remote controllers; Transmission error between main and sub remote controllers
- UETransmission fault between indoor unit and centralized control equipment; Transmission error between the centralized controller and indoor unit
- UFIndoor-to-BS-unit wiring or piping mismatch; Indoor-to-SV-unit wiring or piping mismatch
Outdoor unit12 guides
- E1Circuit board fault; Defective outdoor unit PCB
- E2Current-leakage detection or missing leakage-detection core
- H3Harness abnormality between the outdoor main PCB and inverter PCB
- L1Malfunction of inverter PCB; Inverter PCB abnormality
- L2Momentary power failure during test operation
- L5Inverter instantaneous overcurrent (DC output); Inverter PCB fault
- LCTransmission fault between control PCB and inverter PCB; Transmission error between the inverter PCB and outdoor main PCB
- P1Power voltage imbalance or inverter PCB; Power-supply voltage imbalance
- U2Power supply insufficient or instantaneous abnormality; Insufficient inverter supply voltage
- U3Check operation not executed or transmission error; Test run aborted because of communication issues
- U7Transmission fault between outdoor units or outdoor storage unit; Transmission error between outdoor units
- U9Transmission fault in another system; Another indoor unit on the same F1/F2 line has an error, but the EKVDX or indoor unit can still operate
Whole-system faults5 guides
Codes that depend on the exact model11 guides
- AJMalfunction of capacity setting on indoor unit PCB
- L0Malfunction of inverter system
- L3Electrical parts heat fault
- L4High temperature at inverter circuit heatsink; Malfunction of inverter radiation fin temperature rise
- L6Inverter instantaneous overcurrent (AC output)
- LAMalfunction of power transistor
- M1Malfunction of central remote controller PCB
- M8Transmission fault between optional centralized-control controllers
- PJImproper combination between inverter and fan driver; Malfunction of capacity setting on outdoor unit PCB
- U6Transmission fault between indoor units
- UJTransmission fault with accessory device
Codes can mean different things across model and system families. Every code is in the full lookup for this brand. Last reviewed 2026-08-21.
Is Daikin PCB repair worth it?
Parts and timing
Current residential Daikin parts are well supported locally, but an inverter board or compressor on an older MKS system can materially change the repair decision.Our recommendation
PCB repair is usually sensible when the rest of the system is healthy, the exact board revision is available and testing has ruled out wiring, sensors and connected loads. Daikin systems commonly have a service life of 10–15 years. For a system over 12 years, major component failures usually favour replacement. The unit has exceeded typical lifespan and efficiency has likely dropped. Minor fixes can buy time, but plan for replacement.
If replacement makes more sense, we compare the repair quote with a suitable new system. See our aircon system replacement process.
Other Daikin repair checks
If testing rules out this part, these are the next checks on the same system.
Workmanship warranty
We stand behind the repair we carry out, and we are straight about the part of the cover we do not set ourselves.
Labour
30-day workmanship warranty. If the same fault returns from our repair, we come back and the labour is on us, with no second diagnostic visit fee.
Parts
Parts carry the distributor's warranty for that component, so the term varies by part. We tell you both terms before you approve the work.
Frequently asked questions about Daikin PCB repair in Singapore
What are the signs of a Daikin PCB problem?
How do you confirm a Daikin PCB fault?
Is a Daikin error code enough to order the PCB?
Should I repair or replace my Daikin aircon?
We cover all of Singapore. Find aircon services in your area.
Describe your situation
Tell us what’s going on. Symptoms, setup, photos, anything we should know. We’ll assess and come back with the right next step.