What does the P0 error code mean on a mini-split system?

On many ductless mini-split inverter air conditioning and heat pump systems, the P0 error code typically indicates an inverter module protection fault, an IPM (Intelligent Power Module) error, or an over-current protection trip on the outdoor compressor drive board. This safety code is triggered when the outdoor inverter board detects abnormal electrical currents, voltage spikes, or overheating within the variable-speed drive circuitry, prompting an immediate shutdown to prevent permanent damage to expensive electronic components and compressor windings. You can troubleshoot by checking outdoor power supplies and clearing debris blocking airflow around the heat sink fins. You can verify that the protective fault is addressed when performing a complete ten-minute electrical power reset clears the code, provided that underlying electrical surges or cooling fan restrictions have been fully resolved.