Hyundai Sonata: Engine Control System / Ambient Temperature Sensor (ATS) Description and Operation
Ambient Temperature Sensor (ATS) is installed on the
front-end module and senses the ambient temperature. ECM receives not
only the intake air temperatue but also the ambient air temperature
informations at the same time to control the intake air quantity
precisely provided through the turbo charger. The electrical resistance
of the thermistor decreases as the temperature increases, and increases
as the temperature decreases This sensor has a Negative Temperature
Coefficient (NTC) and its resistance is in inverse proportion to the
temperature.

Inspection
1.
Turn the ignition switch OFF.
2.
Disconnect the IATS connector.
3.
Measure resistance between the IATS terminals 3 and 4.
4.
Check that the resistance is within the speci ...
Specification
Temperature[°C(°F)]Resistance(k?) -40(-40)841.2~1019.3 -20(-4)263.8~306.50(32)92.4~102.810(50)57.0~62.220(68)36.2~38.840(104)15.3~16.750(122)10.3~11.460(140)7.1~8.080(17 ...
Other information:
Hyundai Sonata LF 2014-2019 Service Manual: Description and Operation
Description of ESP
Optimum driving safety now has a name : ESP, the Electronic Stability Program.
ESP recognizes critical driving conditions, such as panic
reactions in dangerous situations, and stabilizes the vehicle by
wheel-individual braking and engine control intervention with no need ...
Hyundai Sonata LF 2014-2019 Service Manual: Heater Core Repair procedures
Replacement
1.
Disconnect the negative (-) battery terminal.
2.
After loosening the bolts remove the main crash pad and cowl cross bar assembly together.
(Refer to Heater -"Heater Unit")
3.
Remove the heater core cover (A) after loosening the mounting screws.
4.
Pull out the heater ...