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 roof drip side finish moulding lh
Remove the 2 roof drip moulding joint covers from
the vehicle body.
Remove the roof drip side finish moulding and no. 2
Center ...
Tc and cg terminal circuit
Description
Connecting terminals tc and cg of the dlc3 causes the skid control ecu to
display 2-digit dtcs by
flashing the abs warning light.
Wiring diagram
Inspection procedure
Check dlc3 (tc voltage)
Turn the ignition switch on.
Measure the voltage of the dlc3.
Standar ...
Installation
Hint:
Use the same procedures for the rh side and lh side.
The procedures listed below are for the lh side.
Install front pillar cover sub-assembly upper lh
Attach the 3 clips to install the pillar cover.
...