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:

General information
A large number of ECU controlled systems are used in the HIGHLANDER. In general, ECU controlled systems are considered to be very intricate, requiring a high level of technical knowledge to troubleshoot. However, most problem checking procedures only involve inspecting the ECU controlled sys ...