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 troubleshootingDriving position memory
This feature automatically
adjusts the driver's seat to
suit your preferences.
Your preferred driving position
(the position of the
driver's seat) can be
recorded and recalled by
pressing a button.
Two different driving positions
can be recorded into
memory.
Each electronic key can be
registered ...
Vin not programmed or mismatch - ecm / pcm
Description
Dtc p0630 is set when the vehicle identification number (vin) is not stored
in the engine control module
(ecm) or the input vin is incorrect. Input the vin with the intelligent tester.
Monitor strategy
Typical enabling conditions
Typical malfunction thresholds
Com ...
Inspection
Inspect engine coolant temperature sensor
Measure the resistance of the sensor.
Standard resistance
Notice:
If checking the sensor in water, be careful not to
allow water to contact the terminals. After
checking, wipe the water off the sensor.
If the result is not as specified, ...