Mini-Split Troubleshooting Card — Error Codes for the Top 5 Brands
A field-reference card for decoding mini-split error codes on LG, Mitsubishi, Daikin, Fujitsu, and Pioneer. Print and keep near the unit.
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Who It's For
Mini-split owners across the Birmingham east corridor who want to know what the blinking lights actually mean before calling.
What's Inside
The top 8 error codes for each of LG, Mitsubishi, Daikin, Fujitsu, and Pioneer. What each one means in plain English. Which ones are safe to reset and which need a tech.
Why It Matters
Most HVAC problems in Birmingham are preventable or fixable cheaply if you know what to look for. This guide tells you what.
Mini-splits are great until they throw a flashing error code that means nothing. Different brand, different code system, no consistency. This card decodes the most common errors on the five brands you're most likely to have in the Birmingham metro. Same format. Same plain English. Same answer to "is this DIY or call a tech?"
This is the field-guide version — the same approach we take when we walk into a service call. No marketing fluff. No upsells dressed up as "tips." Just the working tech's playbook, written down.
A Look Inside
How to read a mini-split error code
Mini-splits indicate faults two ways: a steady or blinking pattern of LEDs on the indoor unit, or a code displayed on a remote with a display screen. The pattern or code maps to a fault category — temperature sensor, refrigerant pressure, communication, fan motor, control board, etc. Each manufacturer uses its own table. The codes below are the most common ones in Birmingham residential service.
LG mini-splits — top 8 codes
- CH 01 — Indoor air temperature sensor open. Sensor or wiring issue. Tech
- CH 02 — Indoor pipe temperature sensor. Sensor failure. Tech
- CH 05 — Indoor/outdoor unit communication error. Often a wiring fault between units. Tech
- CH 06 — Outdoor unit pipe temperature sensor. Tech
- …
Mitsubishi mini-splits — top 8 codes
- P5 — Drain pump float switch activated. Indoor unit drain is clogged. Clean drain line. Often resets itself once drain clears
- P6 — Freeze protection / overheat protection. Filter dirty, indoor airflow restricted. Replace filter, clear coil. Reset
- P8 — Pipe temperature sensor fault. Tech
- E0 — Communication error indoor to outdoor. Tech
- …
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Written by John, 25-year HVAC technician
John has been turning wrenches on Birmingham HVAC systems for 25 years. Alabama HVAC contractor licensed, bonded, and insured. EPA Section 608 Universal certified. He has walked roofs, attics, crawlspaces, and condenser pads across every neighborhood in this metro and has written every guide on this site from the working tech\'s perspective — not the salesman\'s.
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