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SMK & PM (ECM/TCM) Control Module

SMK & PM (ECM/TCM) Control Module (SMARTRA Error) 

G13056595Courtesy of HYUNDAI MOTOR AMERICA

When turning the ignition switch ON or cranking the engine, the engine ECM begins communication with the Smart Key unit (SMK IMMO unit) by sending a VIN (Vehicle Identification Number) request signal to control the engine in a stable manner.

The Smart Key unit sends an "Ignition Approval Not Possible" signal to the engine ECM when the Immobilizer cannot function. In this case, the engine ECM enters an ignition inhibition state and a driver cannot start the engine (ignition or fuel spraying inhibited).

On the other hand, the Smart Key unit sends an "Ignition Approval" signal to the engine ECM including the VIN and learnt status information when the Immobilizer can function.



SMK & PM (ECM/TCM) Control Module (ECM Memory Error) 

G13056596Courtesy of HYUNDAI MOTOR AMERICA

Information regarding an Immobilizer is stored in two separate areas of the EEPROM inside the ECM. The ECM checks both types of the information before the Immobilizer Authentication process. When the ECM confirms that they correspond, the Immobilizer Authentication begins. If they do not, the ECM stops the authentication and store the "ECM Memory Error" DTC. When this occurs, the Limp Home function cannot be performed. If the problem persists after registering a new key, the ECM must be replaced.



SMK & PM (ECM/TCM) Control Module (Authentication Fail) 

G13056597Courtesy of HYUNDAI MOTOR AMERICA

The Smart Key system (SMK) consists of a Smart Key module, power distribution module (PDM), external receiver, and Smart Key holder. On the other hand, the SMK (smart key) system without a FOB holder has an embedded Demodulator which is connected to the SSB with two immobilization coil lines. The Smart Key unit transmits authentic signals to the engine ECM and receives an ignition approval signal to start the engine through this process.



SMK & PM (ECM/TCM) Control Module (Twice overtrial) 

G13056598Courtesy of HYUNDAI MOTOR AMERICA

This function allows a driver to drive the vehicle by turning on the ignition switch twice before registering its key. It can be implemented only when the engine ECM and the Smart Key system (TP, SMK) are virgin. Starting the engine follows the steps below.

  1. For the first ignition ON, remain it between 0.5 and 1.5 sec.
  2. Turn the ignition OFF for 0.2-1.5 sec.
  3. Turn the ignition switch back ON