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 troubleshootingParts location
System diagram
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On-vehicle inspection
Check accelerator pedal rod
Check the voltage.
Connect the intelligent tester to the dlc3.
Turn the ignition switch on
Turn the intelligent tester on.
Select the menu items: diagnosis /
enhanced obd ii / data list / all /
accel pos #1, accel pos #2.
Operate the acceler ...
Driving position memory
Your preferred driving position (the position of the driver’s seat) can
be recorded and recalled by pressing a button.
Two different driving positions can be recorded into memory.
Recording procedure
Check that the shift lever is in p.
Turn the engine switch to the “on” position (ve ...