The temperature will increase by turning the knob to the right.
The temperature will decrease by turning the knob to the left.
Hyundai Elantra AD (2016-2020) Service Manual: Components and Components Location
Component Location
1. Audio unit2. Feeder cable joint connector3. Center speaker4. Glass antenna amplifier5. Front door speaker6. Rear door speaker7. Sub woofer speaker8. Antenna feeder cable9. Tweeter speaker
...
Hyundai Elantra AD (2016-2020) Service Manual: Heated Oxygen Sensor (HO2S) Repair procedures
Inspection
1.
Turn the ignition switch OFF.
2.
Disconnect the HO2S connector.
3.
Measure resistance between the HO2S terminals 2 and 5 [B1/S1].
Measure resistance between the HO2S terminals 3 and 4 [B1/S2].
4.
Check that the resistance is within the specification.
Specification : ...