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: Specifications
Specifications
ItemsSpecificationRated voltageDC 12VOperating voltage9V ~ 16VOperating speed30?/h ~ 250?/hSensible distance70m (Sedan)Curvature radiusStart : More than 125m/30km/hStop : Less than 125mFrequency24 GHzNumbers2EA (Master 1EA, Slave 1EA)
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Hyundai Sonata LF 2014-2019 Service Manual: Components and Components Location
Component Location
1. Power door mirror2. Power door mirror switch3. Power folding mirror switch
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