Immobilizer Control System: Description

The immobilizer system will disable the vehicle unless the proper ignition key is used, in addition to the currently available anti-theft systems such as car alarms, the immobilizer system aims to drastically reduce the rate of auto theft. There are two types of immobilizer. One is a "SMARTRA (SMART TRansponder Antenna)" type and another is a "shinchang" type.

1. SMARTRA type immobilizer
   • The "SMARTRA" type immobilizer system is applied to the 2.0L engine.
   • The SMARTRA system consists of a transponder located in left side cowl cross bar, a coil antenna, a SMARTRA unit, an indicator light and the ECM.
   • The SMARTRA communicates to the ECM (Engine Control Module) via a dedicated communications line. Since the vehicle engine management system is able to control engine immobilization, it is the most suitable unit to control the SMARTRA.
     Fig 1: Identifying SMARTRA Type Immobilizer

     Courtesy of HYUNDAI MOTOR CO.
   • When the key is inserted in the ignition and turned to the ON position, the coil antenna sends power to the transponder in the ignition key. The transponder then sends a coded signal back through the SMARTRA unit to the ECM.
   • If the proper key has been used, the ECM will energize the fuel supply system. The immobilizer indicator light in the cluster will simultaneously come on for more than five seconds, indicating that the ECM has recognized the code sent by the transponder.
   • If the wrong key has been used and the code was not received or recognized by the ECM the indicator light will continue blinking for about five seconds until the ignition switch is turned OFF.
   • If it is necessary to rewrite the ECM to learn a new key, the dealer needs the customer's vehicle, all its keys and the Hi-scan (pro) equipped with an immobilizer program card. Any key that is not learned during rewriting will no longer start the engine.
   • The immobilizer system can store up to four key codes.
   • If the customer has lost his key, and cannot start the engine, contact HMC motor service station.
2. Shinchang type immobilizer
   • The "Shinchang" type immobilizer system is applied to the 2.7L engine.
   • The shinchang system consists of a transponder located in left side cowl cross bar, a coil antenna, an ICM (immobilizer control module), an indicator light and the ECM.
     Fig 2: Identifying Shinchang Type Immobilizer

     Courtesy of HYUNDAI MOTOR CO.
   • When the key is inserted in the ignition and turned to the ON position, the coil antenna sends power to the transponder in the ignition key. The transponder then sends a coded signal back through the coil antenna to the ICM.
   • If the ID code transmitted from the key does not match the pre-registered code in the ICM, injection is not performed by the engine ECM. Hence, each vehicle has a set of keys containing a unique ID code which are registered on the ICM. This signal is captured by the coil antenna located in the front section of the steering handle lock and transmitted to the ICM. The ICM analyses and verifies the signal to determine if the signal matches the pre-registered code. If the signal is verified, the ICM transmits a message to the engine ECM to allow injection. The immobilizer indicator light in the cluster will simultaneously come on for more than five seconds, indicating that the ICM has recognized the code sent by the transponder. If the signal is not verified by the ICM, fuel injection is not performed by the engine ECM. The indicator light will continue blinking for five seconds until the ignition switch is turned OFF. Communication between ICM and ECM communicates through the K-line of ECM. K-line is also used for the communication between ECM and scan tool, there is a regal inside of ICM to switch the communication.
   • If it is necessary to rewrite the ICM to learn a new key, the dealer needs the customer's vehicle, all its keys and the Hi-scan (pro) equipped with an immobilizer program card. Any key that is not learned during rewriting will no longer start the engine.
   • The immobilizer system can store up to four key codes.
   • If the customer has lost his key, and cannot start the engine, contact HMC motor service station.