Hyundai Sonata: Engine Control System / Heated Oxygen Sensor (HO2S) Description and Operation
Heated Oxygen Sensor (HO2S) consists of zirconium and alumina
and is installed both upstream and downstream of the Manifold Catalytic
Converter. The sensor output voltage varies in accordance with the
air/fuel ratio.
The sensor must be hot in order to operate normally. To keep
it hot, the sensor has a heater which is controlled by the ECM via a
duty cycle signal. When the exhaust gas temperature is lower than the
specified value, the heater warms the sensor tip.

Removal
1.
Turn the ignition switch OFF and disconnect the battery negative (-) cable.
2.
Remove the intake manifold (Refer to “Intake And Exhaust System” in EM group).
3.
Disconnect ...
Specification
HO2S [Bank 1/Sensor 1] (Linear type)
ItemSpecificationHeater Resistance (?)2.4 ~ 4.0 [20°C(68°F)]
ItemSpecificationHeater Resistance (?)Approx. 9.0 [20°C(68°F)]
HO2S [Ba ...
Other information:
Hyundai Sonata LF 2014-2019 Owners Manual: Features of Your Vehicle
Satellite radio reception
You may experience difficulties in receiving XM™ satellite radio signals in the
following situations.
If you are driving in a tunnel or a covered parking area.
If you are driving beneath the top level of a multi-level freeway.
If you are driving under a bridge.
If ...
Hyundai Sonata LF 2014-2019 Owners Manual: Underbody maintenance
Corrosive materials used for ice and snow removal and dust control may collect
on the underbody. If these materials are not removed, accelerated rusting can occur
on underbody parts such as the fuel lines, frame, floor pan and exhaust system,
even though they have been treated with rust protectio ...