The engine immobiliser system is designed to prevent the vehicle from being stolen. This system uses a transponder key ecu that stores the key codes of authorized ignition keys. If an attempt is made to start the engine using an unauthorized key, the ecu sends a signal to the ecm to prohibit fuel delivery and ignition, effectively disabling the engine.

The transponder key coil receives this signal, the transponder key amplifier amplifies it, and then the signal is transmitted to the ecu. The ecu matches the key's id code with the vehicle's id code, which was previously registered in the ecu and then communicates the results to the ecm using sfi communication.
Engine immobiliser system
How to proceed with troubleshootingSystem description
General
The front passenger occupant classification system
judges whether the front passenger seat is occupied
or not in accordance with the seat belt buckle
status; and whether the seat is occupied by an adult
or child (with child seat) in accordance with the load
that is applied ...
Installation
Caution:
Be sure to read the precautionary notices concerning the
srs airbag system before servicing it (see page rs-1).
Install roof side rail bracket lh
Install the bracket with the 2 bolts.
Torque: 14 n*m (143 kgf*cm, 10 ft.*Lbf)
Install curtain shield airbag assembly lh ...
Adjusting the mirrors
Make sure that you can see backward clearly by adjusting the inside
and outside rear view mirrors properly.
Caution
Observe the following precautions.
Failure to do so may result in death or serious injury.
Do not adjust the position of the driver’s seat while driving.
Doing so could ...