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 troubleshootingBrake master cylinder
Components
On-vehicle inspection
Check brake fluid level warning switch
Remove the reservoir filler cap and strainer.
Disconnect the brake fluid level warning switch
connector.
Measure the resistance of the switch.
Hint:
There is a float inside the reservoir. Its positio ...
Only rear door lh lock / unlock functions do not operate
Description
The main body ecu receives lock / unlock switch signals and activates the
door lock motor accordingly.
Wiring diagram
Inspection procedure
Inspect rear door with motor lock assembly lh
Apply the battery voltage to the door lock motor and
check the operation of th ...
Pressure sensor circuit
Description
This dtc is output when the refrigerant pressure is either extremely low
(0.19 Mpa [2.0 Kgf/cm2, 28 psi]
or less) or extremely high (3.14 Mpa [32.0 Kgf/cm2, 455 psi] or more). The air
conditioning pressure
sensor, which is installed on the pipe of the high pressure side, detec ...