This warning light illuminates:
Hyundai Sonata LF 2014-2019 Service Manual: A/C Pressure Transducer Components and Components Location
Components Location
1. A/C Pressure Transducer
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Hyundai Sonata LF 2014-2019 Service Manual: Stop Lamp Switch Repair procedures
Adjustment
1.
Turn ignition switch OFF and disconnect the negative (-) battery cable.
2.
Remove the lower crash pad.
(Refer to Body - "Crash Pad")
3.
Remove the knee airbag.
(Refer to Rstraint - "Air Bag Module")
4.
Confirm the gap between stop lamp switch and bracket.
Stop lamp ...