If the Smart Key is not working properly, try replacing the battery with a new one.
Battery Type: CR2032
To replace the battery:
1. Pry open the rear cover of the smart key.
2. Remove the old battery and insert the new battery.
3. Reinstall the rear cover of the smart key.
If you suspect your smart key might have sustained some damage, or you feel your smart key is not working correctly, contact an authorized HYUNDAI dealer.
Information
An inappropriately disposed battery can be harmful to the environment and human health. Dispose the battery according to your local law(s) and regulation(s).
Hyundai Sonata LF 2014-2019 Service Manual: Accelerator Position Sensor (APS) Specifications
Specification
AcceleratorPositionOutput Voltage (V)APS1APS2C.T0.7 ~ 0.80.29 ~ 0.46W.O.T3.85 ~ 4.351.93 ~ 2.18
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Hyundai Sonata LF 2014-2019 Service Manual: Battery Sensor Repair procedures
Removal
1.
Disconnect the battery negative (-) cable.
2.
Disconnect the battery sensor connector (A).
3.
Remove the battery negative (-) cable after removing the bolts (B).
Installation
1.
Install in the reverse order of removal.
Battery sensor cable installation bolt:
10.8 ~ 1 ...