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 troubleshootingDo-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 ...
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 ...
Bleeding
Hint:
If any work is performed on the brake system or if air in the
brake lines is suspected, bleed air from the brake system.
Notice:
Wash off brake fluid immediately if it comes in contact
with any painted surface.
Remove cowl top ventilator louver bracket lh
Detach the 6 claws and ...