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Diagnosis Of Immobilizer Faults: Notes

Communication between the ECM and the SMARTRA.
Function of the SMARTRA and the transponder.
Data (stored in the ECM related to the immobilizer function.

The following table shows the assignment of immobilizer related faults to each type:

TRANSPONDER REFERENCE CHART

Immobilizer Related Faults	Fault types	Diagnostic codes
Transponder key fault	Transponder not in password mode Transponder transport data has been changed.	P1674 (Transponder status error)
Transponder key fault	Transponder programming error	P1675 (Transponder programming error)
SMARTRA fault	Invalid message from SMARTRA to ECM	P1676 (SMARTRA message error)
SMARTRA fault	No response from SMARTRA Antenna coil error Communication line error (Open/Short etc.) Invalid message from SMARTRA to ECM	P1690 (SMARTRA no response)
Antenna coil fault	Antenna coil open/short circuit	P1691 (Antenna coil error)
Immobilizer indicator lamp fault	Immobilizer indicator lamp error (Cluster)	P1692 (Immobilizer lamp error)
Transponder key fault	Corrupted data from transponder More than one transponder in the magnetic field (Antenna coil) No transponder (Key without transponder) in the magnetic field (Antenna coil)	P1693 (Transponder no response error/invalid response)
ECM fault	Request from ECM is invalid (Protocol layer violation-Invalid request, check sum error etc.)	P1694 (ECM message error)
ECM internal permanent memory (EEPROM) fault	ECM internal permanent memory (EEPROM) fault Invalid write operation to permanent memory (EEPROM)	P1695 (ECM memory error)
Invalid key fault	Virgin transponder at ECM status "Learnt" Learnt (Invalid) Transponder at ECM status "Learnt" (Authentication fail)	P1696 (Authentication fail) P1698 (Invalid transponder)
Locked by timer	Exceeding the maximum limit of Twice IGN ON (32 times)	P1699 (Twice IG ON over trial)
Tester (HI-SCAN) fault	Request from tester is invalid (Protocol layer violation-Invalid request, check sum error etc.)	P1697 (Tester message error)

DIAGNOSTIC TROUBLE CODES DTC (LIST)

DTC	Description
P1610	NON-IMMOBILIZER-EMS CONNECTED TO AN IMMOBILIZER
P1674	TRANSPONDER STATUS ERROR
P1675	TRANSPONDER PROGRAMMING ERROR
P1676	SMARTRA MESSAGE ERROR
P1690	SMARTRA NO RESPONSE
P1691	ANTENNA COIL ERROR
P1692	IMMOBILIZER LAMP ERROR
P1693	TRANSPONDER NO RESPONSE ERROR / INVALID RESPONSE
P1694	EMS MESSAGE ERROR
P1695	EMS MEMORY ERROR
P1696	AUTHENTICATION FAIL
P1697	HI-SCAN MESSAGE ERROR
P1699	TWICE OVER TRIAL