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 troubleshootingGeneral information
A large number of ecu controlled systems are used in the
rav4. In general, ecu controlled systems are considered to
be very intricate, requiring a high level of technical knowledge
to troubleshoot. However, most problem checking procedures
only involve inspecting the ecu controlled system's circ ...
Brake pedal load sensing switch
On-vehicle inspection
Inspect brake pedal load sensing switch
Hint:
Do not remove the brake pedal load sensing switch
from the brake pedal support.
When there is a malfunction in the brake pedal load
sensing switch, replace the brake pedal support.
Disconnect the brake pedal l ...
Lost communication with front satellite sensor bus lh
Description
The front airbag sensor lh consists of the diagnostic circuit and the frontal
deceleration sensor.
If the center airbag sensor receives signals from the frontal deceleration
sensor, it determines whether or
not the srs should be activated.
Dtc b1607/84, b1608/84, b1617/84 ...