This indicator light illuminates :
When you select "ECO" mode as drive mode.
WARNING
Do not watch the ECO indicator light while driving. This will distract you and may cause an accident that results in severe personal injury.
Hyundai Sonata LF 2014-2019 Service Manual: AVN Keyboard Repair procedures
Removal
1.
Disconnect the negative (-) battery terminal.
2.
Using a screwdriver or remover, separate the center fascia panel (A).
3.
Remove the center fascia panel (A) after disconnect the connector.
4.
Remove the AVN keyboard unit (A) after loosening the screws.
Installation
1.
...
Hyundai Sonata LF 2014-2019 Service Manual: Injector Troubleshooting
Signal Waveform
The three waveforms below are taken from the #1 and #4
injectors. The top waveform is from the high side (feed side) of the #1
and #4 injectors, while the middle waveform is from the low side (ground
side) of the #1 injector and the bottom waveform is from the low side
of ...