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:

If a warning light turns on or a warning buzzer sounds
Calmly perform the following actions if any of the warning lights comes on or flashes. If a light comes on or flashes, but then goes off, this does not necessarily indicate a malfunction in the system. However, if this continues to occur, have the vehicle inspected by your toyota dealer. Warnin ...