System Diagnosis
Malfunction of transmission between control and inverter PCB
Daikin Packaged
Error Code LC
Troubleshooting guide for the Daikin Packaged system fault LC.
Disclaimer: This information is for general reference. Error codes can vary by model and production year. Always refer to your machine's specific manual and the information printed on the unit itself.
Potential Causes & Solutions
- Defective connection between the inverter PCB and the control PCB.
- External factors (e.g. noise).
- Defective inverter compressor.
- Defective control PCB (transmission block).
Verify Before Replacing Parts
- Confirm the exact Daikin model family and packaged context before acting on a generic code description.
- Confirm board LEDs, wiring polarity, and model compatibility before replacing control boards.
- Check for intermittent communication faults caused by connectors, moisture, or damaged harnesses.
- After the correction, run the system long enough to confirm the code does not return under normal load.
Field Signals to Confirm
What usually confirms it
Loss of comm LEDs, incorrect polarity, or a fault that appears only when indoor and outdoor boards talk.
What can fool you
Board swaps without harness checks can hide the real fault if the wiring path is damaged.
When to Escalate the Call
- Communication faults persist after polarity, harness, and compatibility checks.
- A board replacement seems likely but the full system path has not been confirmed.
Still unsure about this fault?
ACLogics walks you through Daikin Packaged diagnostics step-by-step — so you confirm the cause before swapping parts.
