Samsung Air Conditioner Error Code OUTDOOR_GREEN_FLICKER

The OUTDOOR_GREEN_FLICKER error code on a Samsung air conditioner indicates a Communication NG condition, meaning the communication link between the indoor and outdoor units has failed or is severely degraded. In a split or multi-split system, the indoor and outdoor units continuously exchange control signals over a dedicated communication cable, typically a two or three-conductor wire. When this signal is interrupted, corrupted, or absent, the outdoor unit's green LED enters a flickering state to indicate the fault. The system cannot operate safely without this handshake, so normal cooling or heating functions are suspended.

The communication circuit relies on a properly wired, low-voltage signal line running between the indoor control board and the outdoor control board. Damage to this cable, loose terminal connections, or incorrect wiring are the most frequent physical causes. Beyond the cable itself, a failed control board on either the indoor or outdoor unit can prevent proper signal transmission or reception. Power supply irregularities to either unit's control circuitry can also disrupt communication even when the cable is intact.

Diagnosis begins with a visual and continuity inspection of the communication cable between both units, including the terminal blocks at each end. Technicians should verify that the wire is connected to the correct terminals, that there is no visible damage or pinching along the cable run, and that resistance values across the line are consistent with a continuous, unfaulted conductor. If the cable checks out, attention shifts to the control boards themselves for signs of component damage, burn marks, or failed capacitors.