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
Discharge fuel system pressure (see page
fu-9)
Disconnect cable from negative battery
terminal
Caution:
Wait at least 90 seconds after disconnecting the
cable from the negative (-) battery terminal to
prevent airbag and seat belt pretensioner activation.
Remove radiator support op ...
Reassembly
Bearing position
Standard bearing position
Install differential gear lube apply tube
Install the apply tube and clamp to the transaxle
housing with the bolt.
Torque: 9.8 N*m (100 kgf*cm, 87 in.*Lbf)
Notice:
Make sure to insert the pipe to the stopper.
Instal ...
Communication
Description
When a key is inserted into the ignition key cylinder but no communication
occurs between the key and
transponder key ecu, dtc b2796 is output. When a key is inserted into the
ignition key cylinder but a
communication error occurs between the key and transponder key ecu, dtc b ...