If this warning light comes on while the engine is running, the battery is not being charged. Immediately turn off all electrical accessories. Try not to use electrically operated controls, such as the power windows. Keep the engine running; starting the engine will quickly discharge the battery.
If there is a malfunction with either the alternator or electrical charging system:
1.Drive carefully to the nearest safe location and stop your vehicle.
2.Turn the engine off and check the alternator drive belt for looseness or breakage.
If the belt is adjusted properly, there may be a problem in the electrical charging system.
In this case, have your vehicle inspected by an authorized HYUNDAI dealer.
Hyundai Sonata LF 2014-2019 Owners Manual: Good Driving Practices
Never move the shift lever from P (Park) or N (Neutral) to any other position
with the accelerator pedal depressed.
Never move the shift lever into P (Park) when the vehicle is in motion.
Be sure the vehicle is completely stopped before you attempt to shift into
R (Reverse) or D (Drive).
Do ...
Hyundai Sonata LF 2014-2019 Service Manual: Rear Wheel Speed Sensor Components and Components Location
Components
1. Rear wheel speed sensor2. Rear wheel speed sensor cable
...