Mini-Split Error Codes & Repair Guides
Step-by-step diagnostic guides for Mitsubishi, Daikin, LG, and Pioneer mini-split error codes. Find your brand, find your code, fix your unit.
How to read a mini-split error code
Mini-split systems display error codes on the indoor unit's display or blink them on the operation light. The indoor unit shows the fault; the cause is often in the outdoor unit. The code format varies by brand — Mitsubishi uses numbers like E6, P8; Daikin uses two-character codes like A1, E3; LG uses CH codes; Pioneer uses E or F codes.
Most codes fall into four categories: refrigerant circuit faults (P-codes on Mitsubishi, A/E-codes on Daikin), sensor failures, communication errors between indoor and outdoor units, and protection mode shutdowns. The repair approach differs significantly between these — a refrigerant fault typically requires a licensed HVAC tech, while a communication error may just mean a bad connection you can reseat yourself.
What you can fix vs. what requires a pro
DIY-safe: cleaning the filter and coils, reseating wiring harnesses, resetting the unit, replacing a clogged drain line, checking the outdoor unit for debris or ice. Not DIY-safe: refrigerant checks, pressure testing, capacitor replacement on the outdoor unit PCB. The guides on this site tell you exactly where the line is for each error code.