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 troubleshootingMaster cylinder pressure sensor malfunction
Description
The master cylinder pressure sensor is connected to the skid control ecu in
the abs and traction
actuator.
Dtc c1281/81 can be detected when the master cylinder pressure sensor sends a
master cylinder
pressure signal or test mode ends. Dtc c1281/81 is output only in test mo ...
Installation
Notice:
Do not heat the vehicle body, emblem and name plate
excessively.
Hint:
When installing the emblem and name plate, heat the vehicle
body, emblem and name plate using a heat light.
Standard heating temperature
Install no. 4 Back door name plate (for 4wd)
Clean the vehicle body ...
Motor terminal voltage malfunction
Description
The power steering ecu supplies the current to the power steering motor
through the motor circuit.
Wiring diagram
Inspection procedure
Read value of intelligent tester (motor voltage)
Connect the intelligent tester (with can vim) to the
dlc3.
Turn the ignitio ...