If the key is removed from the ignition switch or placed in the ACC position or the LOCK/OFF position with the headlamps ON, the headlamps (and/or parking lamps) remain on for about 5 minutes. However, if the driver’s door is opened and closed, the headlights are turned off after 15 seconds. However, with the engine off if the driver's door is opened and closed, the headlamps (and/or parking lamps) are turned off after 15 seconds.
The headlamps (and/or parking lamps) can be turned off by pressing the lock button on the remote key or smart key twice or turning the light switch to the OFF or AUTO position. However, if you turn the light switch to the AUTO position when it is dark outside, the headlamps will not be turned off.
You can activate or deactivate the Headlamp Delay function from the User Settings Mode (Light) on the LCD display.
NOTICE
If the driver gets out of the vehicle through other doors (except driver's door), the battery saver function does not operate and the headlamp delay function does not turn off automatically. Therefore, It causes the battery to be discharged. In this case, make sure to turn off the lamp before getting out of the vehicle.
Hyundai Sonata LF 2014-2019 Service Manual: Intake Air Temperature Sensor (IATS) Description and Operation
Description
Intake Air Temperature Sensor (IATS) is included inside
Manifold Absolute Pressure Sensor and detects the intake air
temperature.
To calculate precise air quantity, correction of the air
temperature is needed because air density varies according to the
temperature. So the ECM ...
Hyundai Sonata LF 2014-2019 Owners Manual: Malfunction Indicator Lamp (MIL)
This warning light illuminates:
Once you set the ignition switch or Engine Start/Stop button to the ON position.
- It remains on until the engine is started.
When there is a malfunction with the emission control system. In this case,
have your vehicle inspected by an authorized HYUNDAI dealer ...