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 troubleshootingHandling of hose clamps
Before removing the hose, check the clamp position
so that it can be reinstalled in the same position.
Replace any deformed or dented clamps with new
ones.
When reusing a hose, attach the clamp on the
clamp track portion of the hose.
For a spring type clamp, you may want to spread ...
Reassembly
Hint:
When installing the ornament plate and emblem, heat the
radiator grille, ornament plate and emblem using a heat light.
Standard heating temperature
Notice:
Do not heat the radiator grille, ornament plate and
emblem excessively.
Install radiator grille emblem
Attach ...
Inspection
Inspect engine coolant temperature sensor
Measure the resistance of the sensor.
Standard resistance
Notice:
If checking the sensor in water, be careful not to
allow water to contact the terminals. After
checking, wipe the water off the sensor.
If the result is not as specified, ...