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:

Symptom simulation
HINT: The most difficult case in troubleshooting is when no problem symptoms occur. In such cases, a thorough customer problem analysis must be carried out. A simulation of the same or similar conditions and environment in which the problem occurred in the customer's vehicle should be carried ...