Cee´d(ED) > 2010 > D 1.
6 TCI-U2 > Immobilizer > Immobilizer > P1696 Immobilizer-
Authentication Fail
P1696 Immobilizer-Authentication Fail > General Information
Component Location
General Description
The vehicle immobilizer system consists of the ECM, the SMARTRA3 and ignition keys with built-in transponder.
The ECM carries out the check of ignition key by special encryption algorithm with SMARTRA3 and Transponder.
The encryption algorithm (between ECM and SMARTRA3) is the one offered from BOSCH.
The encryption algorithm (between ECM and Transponder) is Hitag type 2 which is a high level system. With IGN On, the ECM
executes the key Authentication after SMARTRA3 authentication. The Engine can be started when the key authentication is
confirmed by the SMARTRA3.
The Key teaching procedure starts with ECM request of PIN from Scanner. The "virgin“ ECM stores the PIN and the key Learning
can be started. The "learnt“ ECM compares the PIN from tester with the vehicle password in Transponder. If the data are correct,
the key Learning can be started.
Scanner requests the Learning of the first key, the SMARTRA3 is registered at first and then the first key is registered by ECM. If the
SMARTRA3 status is learnt and PIN number is different, the SMARTRA3 will return the incorrect PIN data to the ECM. In this case,
The ECM can’t excute the key learning process.
DTC Description
The ECM sets DTC P1696 if invaild key is inserted into key hole for Authentication
DTC Detecting Condition
Item Detecting Condition Possible Cause
DTC Strategy •
Enable Conditions • IG ON
• Virgin TP at PCM/ECM status “Learnt”
Threshold value • Invalid transponder.
• Learnt(Invalid) TP at PCM/ECM status “Learnt”
Detecting time • Immediately
Fail Safe •-
Diagnostic Circuit Diagram
P1696 Immobilizer-Authentication Fail > Scantool Diagnostics
Monitor Scantool Data
1. Check status
(1) IGN "ON" & Engine "OFF"
(2) Monitor the "ECM, Key and Smartra Status" Parameter on the Scantool.
Specification : 'LEARNT'
Fig.1) This data show that 3 keys have been taught, ECU has been learnt, Key in key cylinder has been learnt and
SMARTRA3 has been learnt
(3) Have both the ECM and KEY status been learnt ?
▶ Substitute with known good "virgin" transponder and go to "Component Inspection" Procedure.
▶ Go to "Component Inspection" Procedure.
P1696 Immobilizer-Authentication Fail > Inspection/Repair > Component Inspection
Component Inspection
1. Check transponder
(1) IGN "ON" & Engine "OFF"
(2) Neutralize ECM and Register transponder key by scantool.
Pin code is requied to Neutralize ECM and to Register transponder key
(3) Are Neutralizing and Registering completed normally ?
▶ Check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or
damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.
▶ Substitute with a known-good transponder and perform key teaching procedure with scanner.
▶ If the problem is corrected, replace transponder and then go to "Verification of Vehicle Repair" procedure.
P1696 Immobilizer-Authentication Fail > Verification of Vehicle Repair
Verification of Vehicle Repair
After a repair, it is essential to verify that the fault has been corrected.
1. Connect scantool and selet "Diagnostic Trouble Codes(DTCs)" mode and then clear DTC
2. Operate the vehicle and monitor the DTC on the scantool
3. Are any DTCs present?
▶ Go to the applicable troubleshooting procedure
▶ System is performing to specification at this time.
