CH05

Indoor to outdoor unit communication error

Home Appliance Error Codes LG Air conditioners Short guide

Can you still use it? No, unplug it

Typical cost Under SAR 1,500

What it means

On LG units, CH05 commonly means communication between the indoor and outdoor units has failed, so the outdoor unit does not run and there is no cooling. The meaning can vary by model, so check the manual for your unit.

Symptoms3

Air from the indoor unit is not cold.
The outdoor unit is idle.
The code appears shortly after start-up.

Possible causes4

Broken communication cable or loose or miswired terminals.
No power to the outdoor unit.
Failed indoor or outdoor control board.
Low or unstable supply voltage.

How to diagnose and fix4

Switch the breaker off for two minutes, then restart.
Make sure the outdoor unit breaker has not tripped.
Have a technician check the wiring, terminals and boards.
Do not open the wiring panel while the unit is powered.

Repair cost

0–200

200–600

600–1,500

1,500+

In Saudi riyals; the highlighted part is the expected range for this fault.

Wiring repairs are cheap; a control board is what drives the cost up.

Prices are rough estimates including the part and the technician’s fee, and vary with brand, model and part source.

Frequently asked questions

Can it appear after a power cut?

It may show briefly; if it clears after a restart there is no need to worry.

Is the board usually to blame?

Not always; wiring and terminals are a common cause and should be checked first.

This guide is for information only and does not replace an inspection by a qualified technician. If the fault involves brakes, steering, engine temperature, electrics or refrigerant, do not attempt the repair yourself.

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