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 troubleshootingRemoval
Hint:
Use the same procedures for the rh side and lh side.
The procedures listed below are for the lh side.
Remove rear wheel
Remove rear stabilizer link assembly lh
Remove the nut and disconnect the link from the
suspension no. 2 Arm.
Remove the nut and link from the sta ...
Operation check
Check electrical door lock operation
Check the basic function.
Check that all doors lock when the door control
switch (for manual operation) is turned to lock
and all doors unlock when turned to unlock.
Check that all doors lock when the driver side
door lock key cylinder is t ...
Opening the fuel tank cap
Pull up the opener to open the
fuel filler door.
Turn the fuel tank cap slowly to
open.
Hang the fuel tank cap on the
back of the fuel filler door.
...