What CH03 Means
CH03 indicates a problem with the wired remote control, per LG's dedicated CH03/CH04 troubleshooting article, caused by a faulty remote, wiring issues, or a main circuit board error.
Common Causes of CH03
- Faulty wired remote control
- Wiring issue between the remote and the unit
- Main circuit board error
🔧 One Safe Check You Can Try
Unplug the air conditioner, or turn off its circuit breaker if you can't reach the plug, wait about five minutes, then restore power and check whether the error code has cleared.
⚠ Why You Shouldn't Go Further Than That
- Do not disassemble the air conditioner or replace internal parts yourself - LG's warning for this code states doing so may cause fire, electric shock, serious injury, or death.
- If CH03 persists after a reset, stop using the unit and contact LG Support rather than repeating the reset.
Opening a panel to inspect or repair something yourself doesn't automatically cancel your manufacturer's warranty — but it can risk accidental damage, and some manufacturers do have specific service conditions. Check your product's warranty terms, or ask us, before deciding.