Smart Key registration error: "Registration failed, Smartkey security has not been released"

Symptom

When attempting to perform the Smart Key registration function, the registration fails with the message “Registration failed” along with “Smartkey security has not been released.”

Cause

If the Smart Key registration function is performed while the ignition is ON (IG ON) instead of OFF (IG OFF), the security authentication is not properly released, resulting in a security authentication failure.

How to Resolve

1. Log out of the diagnostic app.
2. Completely close the diagnostic app.
3. Restart the diagnostic app.
4. Log back into the diagnostic app.
5. Switch the vehicle to IG OFF state, then perform the Smart Key Registration (key registration) function again.