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 troubleshootingInspection
Inspect oil pump assembly
Turn the drive gear with 2 screwdrivers and make
sure it rotates smoothly.
Notice:
Be careful not to damage the oil seal lip.
Inspect clearance of oil pump assembly
Push the driven gear to one side of the body. Using
a feeler gauge, measur ...
Dtc check / clear
Check dtc
Hint:
When dtc b1650/23 is detected as a result of
troubleshooting for the airbag system, troubleshoot
the occupant classification system.
Use the intelligent tester (with can vim) to read and
clear dtcs, otherwise the dtcs cannot be read and
cleared.
Connect ...
Disassembly (2006/01- )
Remove front axle inboard joint boot no. 2
Clamp
One touch type:
using a screwdriver, remove the no. 2 Inboard joint
boot clamp, as shown in the illustration.
Claw engagement type:
using needle-nose pliers, remove the no. 2 Inboard
joint boot clamp, as shown in the illustra ...