This indicator light illuminates:
This indicator light blinks:
While the ESC is operating.
Hyundai Sonata LF 2014-2019 Service Manual: Ambient Temperature Sensor Repair procedures
Inspection
1.
Check the resistance of the ambient temperature sensor
between terminals 1 and 2 whether it changes by changing the ambient
temperature.
1. Ambient Sensor (+)2. Sensor ground
Specification
Ambient temperature[°C (°F)] Resistance between terminal 1 and 2 (k?)-40 (-40)88 ...
Hyundai Sonata LF 2014-2019 Owners Manual: Explanation of Scheduled Maintenance Items
Engine Oil and Filter
The engine oil and filter should be changed at the intervals specified in the
maintenance schedule. If the car is being driven in severe conditions, more frequent
oil and filter changes are required.
Drive Belts
Inspect all drive belts for evidence of cuts, cracks, excessive ...