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 troubleshootingShift lock system
Parts location
System diagram
On-vehicle inspection
Check shift lock operation
Move the shift lever to p.
Turn the ignition switch off.
Check that the shift lever cannot be moved to any
position other than p.
Turn the ignition switch on, depress the brake
pedal and chec ...
Transponder chip malfunction
Description
This dtc is output when: 1) during key code registration, a key malfunction
occurs; 2) the key code was
unable to be registered properly.
Inspection procedure
Reregister key
Clear the dtc (see page ei-18).
Reregister the key code with the transponder key ecu
(s ...
Terminals of ecu
Check transponder key amplifier
Disconnect the e5 amplifier connector.
Measure the resistance of the wire harness side
connector.
If the result is not as specified, there may be a
malfunction in the wire harness.
Reconnect the e5 amplifier connector.
Measure the resist ...