Hyundai Sonata: Lane keeping Assist System (LKAS) / LKAS operation

To activate/deactivate the LKAS:

With the ignition switch in the ON position, press the LKAS button located on the instrument panel on the lower left hand side of the driver.

he indicator in the cluster display will initially illuminate white.

When the indicator(white) activated in the previous ignition cycle, the system turns on without any control.

If you press the LKAS button again, the indicator on the cluster display will go off.

The color of indicator will change depend on the condition of LKAS.

- White : Sensor does not detect the lane marker or vehicle speed is less than 40 mph (64 km/h).
- Green : Sensor detects the lane marker and system is able to control the steering.

LKAS activation


The Lane Keeping Assist System is a system to help prevent the driver from leaving the lane. However, the driver should not solely rely on the system but always check the road conditions when driving.

If the speed of the vehicle is over 40 mph (64 km/h) and the system detects lane markers, the color changes from gray to white.

If the speed of the vehicle is over 40 mph (64 km/h) and the system detects lane markers, the color changes from gray to white.

When the conditions below are met, LKAS will be enable to assist steering.

If LKAS can assist steering, a green steering wheel indicator will illuminate.

If the vehicle moves out its lane because steering torque for assistance is not enough, the line indicator of deviation direction will blink.

Keep hands on steering wheel

If the driver takes hands off the steering wheel for several seconds while the LKAS is activated, the system will warn the driver.


Driver's grasp not detected. LKAS will be disabled temporarily

If the driver still does not have their hands on the steering wheel after several seconds, the system will not control the steering wheel and warn the driver only when the driver crosses the lane markers.

However, if the driver has their hands on the steering wheel again, the system will start controlling the steering wheel.

Lane keeping Assist System (LKAS)
The Lane Keeping Assist System helps detect the lane markers on the road with a camera at the front windshield, and assists the driver's steering to help keep the vehicle in the lanes. When the sys ...

LKAS malfunction
Check LKAS LKAS failure indicator The LKAS failure indicator (yellow) will illuminate if the LKAS is not working properly. Have your vehicle checked by an authorized HYUNDAI dealer. WARNING The dr ...

Other information:

Hyundai Sonata LF 2014-2019 Owners Manual: Smart key precautions
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Hyundai Sonata LF 2014-2019 Service Manual: Troubleshooting
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