Ductless mini-split indoor head mounted high on a wall

Mini-split indoor unit blinking light (reading the code)

A blinking pattern is a fault code. Count the blinks before you reset power, because a breaker reset erases the code. Then look it up for the brand and fix the cause.

Cross-checked ~30 min moderateBrands: Mitsubishi Electric, Daikin, Fujitsu, LG, MrCool, Pioneer

Before you start

Outdoor inverter units store high DC voltage after power-off; wait for the board LED to go out before touching.
Refrigerant codes (leak, low charge) are EPA 608 work: refer.

Diagnostic steps

Unlock all 4 steps with expected values

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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