You can start the engine without inserting the key.
NOTICE
To prevent damaging the smart key:
NOTICE
Always have the smart key with you when leaving the vehicle. If the smart key is left near the vehicle, the vehicle battery may be discharged.
Hyundai Sonata LF 2014-2019 Service Manual: Stop Signal Electronic Module Specifications
Specifications
CategoryDataOperation temperature range (°C)-40 ~ 85Preserving temperature range (°C)-40 ~ 105Operating voltage (V)5.8 ~ 16Rated current (A)15
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Hyundai Sonata LF 2014-2019 Owners Manual: Smart Key
Your HYUNDAI uses a Smart Key, which you can use to lock or unlock a door (and
trunk) and even start the engine.
1. Door Lock
2. Door Unlock
3. Trunk Open
4. Panic
Locking
To lock :
1. Close all doors, engine hood and trunk.
2. Either press the door handle button or press the Door Lock button (1) ...