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 troubleshootingBlower motor circuit
Description
When the heater control (blower switch) is set to position 1 or higher, the
contact of the htr relay is
closed, current flows to the blower motor, and the blower motor operates. The
blower motor speed can be
changed by exchanging the ground and the blower resistor circuit with the ...
Removal
Drain differential oil
Remove rear wheel
Remove tailpipe assembly
Remove the tailpipe (see page ex-2).
Remove center exhaust pipe assembly
Remove the center pipe (see page ex-2).
Remove propeller with center bearing
shaft assembly (see page pr-3)
Remove rear suspen ...
Dtc check / clear
Check dtc
Connect the intelligent tester (with can vim) to the
dlc3.
Turn the ignition switch on and turn the intelligent
tester on.
Read the dtc by following the prompts on the
tester screen.
Hint:
Refer to the intelligent tester operator's manual for
further details.
...