General Information

Component Location





General Description

The SMARTRA carries out the communication with the built-in transponder of the ignition key. This wireless communication runs by RF (Radio frequency of 125 kHz). The SMARTRA is mounted at the ignition lock close to the antenna coil for RF transmission and receiving.
The RF signal from the transponder received by the antenna coil is converted into messages for serial communication by the SMARTRA device. And the received messages from the EMS are converted into the RF signal, which is transmitted, to the transponder by antenna.
The SMATRA executes the encryption algorithm and transmits the encryption result. And SMARTRA is in charge of relaying from EMS to Transponder.
The SMARTRA is taught in key learning process and stores the DPN (converted from PIN) in memory inside SMARTRA. This DPN (converted from PIN) is used in encryption algorithm between EMS and SMARTRA and to neutralize the SMARTRA. When SMARTRA is neutral, old DPN (converted from PIN) and SEK (generated from DPN) are deleted.
New DPN (converted from PIN) can be stored in Neutral SMARTRA.
The SMATRA Learning is possible in case that the status of SMARTAR is "virgin" or "neutral ". In case that the SMARTRA3 is "learnt", the SMARTRA will transmits the information whether DPN (converted from PIN) inputted from tester is same as the DPN (converted from PIN) in SMARTRA.
The SMARTRA Learning is possible regardless of key status.
The SEK (generated from DPN) is used in encrypted communication between SMARTRA and EMS. The SEK (generated from DPN) is made from DPN (converted from PIN) inputted during SMARTRA3 Learning.
If the SMARTRA is learnt, the SEK (generated from DPN) will be stored in EEPROM. The EMS stores the SEK (generated from DPN) in EEPROM in case that one more key is taught validly.
If the DPN (converted from PIN) inputted from EMS fail over 3 trials (3trials: continuously or intermittently), the EMS will not accept the request of key Learning for an hour.
Disconnecting the battery or other manipulation cannot reduce this time. After the connecting of battery to EMS the timer starts again for one hour

DTC Description

The PCM/ECM sets DTC P169A if authentication between PCM/ECM and SMARTRA has been failed

DTC Detecting Condition





Schematic Diagram