Samsung Mini Split C458 Error Code
Check your model first
The source record does not specify an exact model family.
Match the model on your equipment label to the linked manufacturer documentation. The same code can mean different things across model families.
Quick answer
C458 on a Samsung mini split is an EEPROM data error between the main and inverter Micom. Reset once; if C458 returns, the board needs a technician.
Severity: medium · DIY difficulty: easy
Safety
Stop at the breaker power-cycle and any plug-accessible checks (filters, remote settings, visible wiring). The outdoor unit's capacitor holds a lethal charge and the refrigerant circuit is both pressurized and (on R-32 units) flammable — opening panels or servicing the sealed system is licensed-technician work (EPA 608).
What C458 means
C458 means EEPROM data exchanged between the main Micom and inverter Micom is bad or unreadable - a control-board memory/communication fault. Samsung WindFree Premium service manual: EEPROM data error (main Micom <-> inverter Micom).
First checks before service
1. One-time fault event (power disturbance or transient sensor reading) common DIY
Check: Power-cycle at the breaker/disconnect (or unplug for CPAP), restore, and run the system while watching for the code.
Fix: If the code does not return after a full run cycle, the fault was transient — monitor, no repair needed.
2. Fault persists after a clean reset occasional pro only
Check: If the code returns immediately or every session, note the conditions (startup, heating, after rain).
Fix: A persisting code points at the component the manual assigns to this code — that repair is technician territory.
Related codes
Sources
- Samsung C458 error code - SplitAtlas — verified 2026-08-29
- Samsung AC Error Codes (E/C prefix mapping, E4xx drive family) - Be Cool Air Conditioning — verified 2026-08-29
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