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Engine Immobiliser System (w/o Smart Key System)





ENGINE IMMOBILISER: ENGINE IMMOBILISER SYSTEM (w/o Smart Key System): SYSTEM DIAGRAM










SYSTEM DESCRIPTION

1. ENGINE IMMOBILISER SYSTEM DESCRIPTION

The engine immobiliser system is designed to prevent the vehicle from being stolen. This system uses the transponder key ECU assembly that stores the key codes of authorized ignition keys. If an attempt is made to start the hybrid control system using an unauthorized key, the ECU sends a signal to the hybrid vehicle control ECU to prohibit fuel delivery and ignition, effectively disabling the hybrid control system.

2. FUNCTION OF MAIN COMPONENT





3. SYSTEM FUNCTION

(a) When the transponder key ECU assembly detects that the key unlock warning switch is on, the transponder key ECU assembly provides current to the transponder key coil and produces an electric wave. A transponder chip in the key grip receives the electric wave. Upon receiving the electric wave, the transponder chip outputs a key ID code signal. The transponder key coil receives this signal, which is amplified by the transponder key amplifier, and the signal is transmitted to the transponder key ECU assembly.

The ECU matches the key's ID code with the vehicle's ID code, which was previously registered in the ECU, and communicates the results to the hybrid vehicle control ECU.

After the identification results show that the key's ID code matches the vehicle's ID code and the transponder key ECU assembly has confirmed their match: 1) the engine immobiliser system does not immobilize the hybrid control system and the hybrid control system controls enter standby mode; and 2) the ECU transmits a security indicator light signal that communicates "indicator light off" to the clock. Then, the clock turns off the security indicator light.

(b) The security indicator light pattern is as shown below (when changing from the immobiliser set status to the unset status):