Security Indicator Light Circuit: Description
WARNING: This page is about a different car, the 2007 Toyota Land Cruiser. However, it is still accessible from the selected car via links, so may be relevant.
When the theft deterrent system is preparing to be set, the security indicator light turns ON. When the system is set, the security indicator light blinks. It also indicates the condition of the engine immobilizer system according to the request from the transponder key ECU assembly.