Toyota Highlander Service Manual: Sliding roof/convertible

Engine immobilizer system

REGISTRATION 1. DESCRIPTION OF CODE REGISTRATION (a) When adding master keys and sub-keys (additional registration).  Register the key code (immobilizer code) in the transponder key ECU. ...

Sliding roof system

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More about Toyota Highlander:

Engine immobilizer system
The vehicle’s keys have built-in transponder chips that prevent the engine from starting if a key has not been previously registered in the vehicle’s on-board computer. Never leave the keys inside the vehicle when you leave the vehicle. This system is designed to help prevent vehicle the ...