How to Replace the Key Fob Battery in a Hyundai Elantra Hybrid

Steps from the 2026 Hyundai Elantra Hybrid owner's manual (Smart key (battery type CR2450); the remote key variant uses a CR2032 battery).

Put a slim tool into the key hole (1) to pry open the rear cover of the smart key.
Remove the old battery.
Insert the new CR2450 battery, making sure its position is correct.
Reinstall the rear cover of the smart key.

Battery Type: CR2450 for the smart key.
An improperly positioned battery may discharge the battery, causing smart key failure.

Source: 2026 Hyundai Elantra Hybrid owner's manual, PDF page 161. Steps are summarized in our own words (AI-assisted, checked against the cited pages 2026-10-18). Other model years can differ; your manual has the final word.

Confirm with your own manual, dipstick or door-jamb label.
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