If you own a KIA Optima manufactured between 2004 and 2008, you might have noticed that the air conditioning system doesn't always remember your last setting for internal air circulation. This can be annoying, especially if you prefer the cabin to recirculate air by default when starting the engine—particularly in hot, dusty, or polluted environments.
Luckily, there's a hidden sequence that allows you to set the internal (recirculated) airflow as the default when the car starts. Here's a step-by-step guide on how to do it:
1. Set the Fan Speed to Zero
Turn off the A/C fan completely by adjusting the fan speed dial to the 0 position. This is important as the sequence won't work if the fan is active.
2. Press the Defroster Button
Tap the defrost button (usually marked with a windshield icon and upward arrows). This step helps the system enter configuration mode.
3. Press the Internal/External Air Flow Button Five Times
Find the Internal/External Air Flow button (usually marked with a car and an arrow looping inside or passing through it).
Press it five times. You should see the indicator light start blinking and then stay solid. This confirms the system has accepted the input.
4. Press the Button Again to Set Internal Airflow
After the light stays solid, press the button once more to confirm that internal airflow is selected.
5. Test It Out
Turn off the engine, then turn it back on to see if the setting sticks.
If the internal airflow is still selected, congratulations—you've successfully set it as the default.
Why Use Internal Airflow?
Using internal (recirculated) air can help:
Final Notes
This setting is not widely documented in the user manual, so consider it a useful trick for improving your driving comfort. If the setting doesn't stay saved after engine restart, try repeating the process carefully—especially step 3, which must be done precisely.
Now your KIA Optima knows your preference—cool and clean air from the inside, every time you drive.