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 troubleshootingSystem description
General
This system has the following functions: manual slide
open and close; auto slide open and close; manual tilt up
and down; auto tilt up and down; jam protection; and key
off operation.
Function of main component
System operation
The sliding roof has the following ...
Registration
Notice:
The vehicle identification number (vin) must be input
into the replacement ecm.
Hint:
The vin is a 17-digit alphanumeric number. The intelligent
tester is required to register the vin.
Description
This registration section consists of 3 parts: input
instructions, read vin and wr ...
Symptom simulation
Hint:
The most difficult case in troubleshooting is when no
problem symptoms occur. In such a case, a thorough
problem analysis must be carried out. A simulation of the
same or similar conditions and environment in which the
problem occurred in the customer's vehicle should be
carried out. No ...