General Information

Component Location





General Description

Immobilizer is device that prevents car from being thieved by reproduced key. Major components of immobilizer are Transponder, PCM/ECM (Engine Control Module) and SMARTRA. Besides them, Immobilizer has transponder and coil antenna in it.
If driver inserts key into key hole, SMARTRA gets transponder signal by wireless communications run by Radio frequency of 125kHZ via coil antenna and 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 SMARTRA executes the encryption algorithm and transmits the encryption result to PCM/ECM through K-line communication line.
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. If the SMARTRA3 statue is virgin/neutral, the SMARTRA stores DPN (converted from PIN) in EEPROM and transmits the success message of the DPN (converted from PIN) storage. (If the SMARTRA3 is learnt, the SMARTRA3 compares DPN (converted from PIN) transmitted by the EMS with DPN (converted from PIN) stored in EEPROM and transmits the (in)correct DPN (converted from PIN) message to EMS)
If the SMARTRA is learned normally or the DPN (converted from PIN) of the registered SMARTRA is same as the EMS, the EMS begins operation the Transponder Learning.
If the Learning of the first transponder, the EMS stores the DPN (converted from PIN) in its EEPROM and converts state into learnt state.
Then PCM/ECM deciphers code in it. If inserted key has invalid transponder with incorrect code or doesn't have transponder in it, PCM/ECM judges that inserted key is reproduced key and prohibits engine starting.

DTC Description

The ECM sets DTC P1610 if Non Immobilizer EMS is installed on vehicle equipped with Immobilizer.

DTC Detecting Condition





Diagnostic Circuit