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 troubleshootingChecking the battery
Check the battery as follows.
â– Battery exterior
Make sure that the battery terminals
are not corroded and that
there are no loose connections,
cracks, or loose clamps.
Terminals
Hold-down clamp
â– Before recharging
When recharging, the battery produces
hydrogen gas which is flammable
and exp ...
Do-it-yourself service
precautions
If you perform maintenance by yourself, be sure to follow the
correct procedure as given in these sections.
Caution
The engine compartment contains many mechanisms and fluids that may
move suddenly, become hot, or become electrically energized. To avoid death
or serious injury, obse ...
Back door
The back door can be locked/unlocked and opened/closed by
the following procedures.
Locking and unlocking the back door
Door lock switch
Entry function (if equipped)
Wireless remote control
Opening/closing the back door from inside the vehicle (vehicles
with a power back door)
Press a ...