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 troubleshootingFront passenger side satellite sensor bus initialization incomplete
Description
When the center airbag sensor receives signals from the lateral deceleration
sensor, it determines
whether or not the srs should be activated.
Dtc b1648/82 is recorded when a malfunction is detected in the rear airbag
sensor rh circuit.
Wiring diagram
Inspection pr ...
Rear occupant classification sensor rh collision detection
Description
Dtc b1788 is output when the occupant classification ecu receives a collision
detection signal sent by
the rear occupant classification sensor rh when an accident occurs.
Dtc b1788 is also output when the front seat rh is subjected to a strong impact,
even if an actual
acci ...
Eps warning light circuit
Description
If the power steering ecu detects a malfunction, the p/s warning light comes
on. At this time, the power
steering ecu stores a dtc in its memory.
Wiring diagram
Inspection procedure
Check for dtc
Using the intelligent tester (with can vim), check for
dtcs and confir ...