
Downloaded from www.Manualslib.com manuals search engine Immobilizer Control System:  10C-6
Diagnostic Trouble Code (DTC) ClearanceS7RS0BA304003
NOTE
To know how to use SUZUKI scan tool in 
detail, refer to its operator’s manual.
 
Using Scan Tool
1) Turn the ignition switch to OFF position,
2) Connect SUZUKI scan tool to data link connector  (DLC) (1) located under instrument panel at driver’s 
seat side.
Special tool
(A):  SUZUKI scan tool 3) Turn the ignition switch to ON position.
4) Clear DTC(s) according to the instructions displayed 
on SUZUKI scan tool.
5) After completing the clearance, turn the ignition  switch to OFF position, and then disconnect SUZUKI 
scan tool from DLC.
Using Diagnosis Connector (If Equipped)
Refer to “Without Using Scan Tool” under “DTC 
Clearance in Section 1A”.
Diagnostic Trouble Code (DTC) TableS7RS0BA304004
ECM
NOTE
If any DTC other than the above DTCs is detected, refer to “DTC Table in Section 1A”. 
 
(A)1
I4RS0BA30003-03
DTC No. Detecting Item Detecting ConditionImmobilizer 
Indicator Lamp
P1614 Transponder Response Error Transponder code in the transponder built in 
the ignition key cannot be read through ICM.Flash
P1615 ID Code Does Not Re
gistered (Vehicle 
equipped with Keyless Start System only) • While registering the transponder code in 
the transponder built in the ignition key in 
ECM, the keyless start control module 
sent a signal to ECM indicating that the ID 
code could not be registered.
• The ID code could not be registered in the  keyless start control module or ECM. Flash
P1616 Different Registration ID Codes (Vehicle 
equipped with Keyless Start System only) ECM detects different ID codes registered in 
ECM and keyless start system.
Flash
P1618 CAN Communication Error (Reception Error 
for Keyless Start Control Module) (Vehicle 
equipped with Keyless Start System only) Reception error communication data for 
keyless start control module is detected for 
longer than specified time continuously.
Flash
P1621 Immobilizer Commu nication Line ErrorCommunication error between ICM and 
ECM is detected by ECM. Flash
P1622 EEPROM Reading / Writing Error EEPROM in ECM is corrupted.Flash
P1623 Unregistered Transponder Transponder code in the transponder built in 
the ignition key is invalid.Flash
P1625 Immobilizer Antenna Error ICM is faulty.Flash
P1636 Immobilizer Information Registration Failure Communication error between ECM and 
BCM is detected by ECM.No operation
P1638 Immobilizer Info rmation Mismatched • Communication error between ECM and 
BCM is detected by ECM
• Wrong ECM or BCM is used. No operation  

Downloaded from www.Manualslib.com manuals search engine Immobilizer Control System:  10C-10
DTC Confirmation Procedure1) Register the transponder code in the transponder in the  ignition key with ECM referring to “Registration of the 
Ignition Key”.
2) Check DTC in ECM.
Troubleshooting
DTC P1616: Different Registration ID Codes (Vehicle equipped with keyless start system only)S7RS0BA304010
Circuit Description
P1616 is detected when ECM detects different ID codes registered in ECM and keyless start control module after 
turning engine start knob to ON position.
Normally, when keyless start control module is replaced with new one, ECM automatically registers blank ID code of 
keyless start control module to applicable one  after turning ignition switch to ON position.
However, when keyless start control module is replaced wit h used one, ECM does not automatically register old ID 
code of keyless start control module to applicable one ev en if ignition switch is turned to ON position.
Step Action Yes No
1 Was “Immobilizer Control S ystem Check” performed? Go to Step 2. Go to “Immobilizer 
Control System Check”.
2 Registration of Ignition Key
1) Register ignition key in use with ECM referring to 
“Registration of the Ignition Key”.
Was registration of ignition key completed? Unregistration of remote 
controller ID code.
Go to Step 3.
3 DTC check of ECM
Is DTC detected other than P1615? Go to applicable DTC 
diag. flow.
Go to Step 4.
4 DTC check of keyless start control module
1) Check keyless start control  module for DTC referring to 
“DTC Check in Section 10E”.
Is DTC detected? Go to applicable DTC 
diag. flow.
Go to step 5.
5 Check for communication circuit between steering lock 
unit and keyless start control module
1) With the ignition switch at OFF position, disconnect 
steering lock unit connector and keyless start control 
module connector.
2) Check for proper connection  at terminals and wires of 
each connector referring to “Intermittent and Poor 
Connection Inspection in Section 00”.
3) If OK, check for open, short, and high resistance in each  circuit between steering lock unit and keyless start 
control module. Refer to  step 2 in “DTC No. 11: 
Communication Error with Steeri ng Lock Unit in Section 
10E”.
Is each circuit in good condition? Go to Step 6. Repair malfunction part.
6 Steering lock unit power supply check
1) Connect keyless start control module connector.
2) With ignition switch at ON position, check voltage 
between power supply terminal and ground terminal of 
steering lock unit connector.
Is voltage 4 – 6 V? Replace steering lock 
unit.
Substitute a known-
good keyless start 
control module and 
recheck. If DTC P1615 
is still detected, 
substitute a known good 
ECM and recheck.  

Downloaded from www.Manualslib.com manuals search engine 10C-11 Immobilizer Control System: 
Detecting Condition and Trouble Area
DTC Confirmation Procedure1) Engine start knob turn to ON position.
2) Check DTC for ECM.
Troubleshooting
DTC P1618: CAN Communication Error (Reception Error for Keyless Start Control Module) (Vehicle 
equipped with keyless start system only)
S7RS0BA304011
Detecting Condition and Trouble Area
DTC Confirmation Procedure 1) Turn Ignition switch to ON position.
2) Check DTC for ECM.
Troubleshooting Detecting Condition Trouble Area
ECM detects different ID codes registered in ECM and 
keyless start control module. • Keyless start control module
•ECM
Step
Action YesNo
1 Was “Immobilizer Control S ystem Check” performed? Go to Step 2.Go to “Immobilizer 
Control System Check”.
2 Registration of the Ignition Key
1) Clear DTC referring to “Diagnostic Trouble Code (DTC) 
Clearance”.
2) Register ignition key with ECM referring to “Registration  of the Ignition Key”.
Is ignition key able to be registered? Go to Step 3.
Go to Step 4.
3 Keyless start system operation check
Engine start using keyless start system.
Does engine start? Unregistration of remote 
controller ID code.
Check DTC for ECM. 
When DTC is detected, 
go to applicable DTC.
4 DTC check of ECM
Check DTC for ECM.
Is DTC P1618 and/or P1615 detected other than P1616? Go to DTC P1618 
troubleshooting.
Go to DTC P1615 
troubleshooting.
Detecting Condition
Trouble Area
Reception error of communication data for keyless start 
control module is detected for longer than specified time 
continuously. • CAN communication circuit
• Combination meter
• Keyless start control module
•BCM
•ECM
• ABS/ESP®
 control module
Step Action YesNo
1 Was “Immobilizer Control S ystem Check” performed? Go to Step 2.Go to “Immobilizer 
Control System Check”.
2 DTC check of ECM
Is DTC P1674, P1675, P1678 and/or P1685 detected 
together? Go to applicable DTC 
diag. flow.
Go to Step 3.  

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DTC P1621: Immobilizer Communication Line ErrorS7RS0BA304012
Detecting Condition and Trouble Area
DTC Confirmation Procedure1) Ignition switch turn to ON position.
2) Check DTC for ECM.
Troubleshooting 3
DTC check of BCM
Check BCM for DTC referring to “DTC Check in Section 
10B”.
Is DTC U1073, U1100 and/or U1144 detected? Go to applicable DTC 
diag. flow.
Go to Step 4.
4 Control module connector check
1) Check connection of connectors of all control modules 
communicating by means of CAN.
2) Recheck DTC.
Is DTC P1618 detected? Go to Step 5. Intermittent trouble. 
Check for intermittent 
referring to “Intermittent 
and Poor Connection 
Inspection in Section 
00”.
5 CAN communication circuit check
1) Turn ignition switch to OFF position.
2) Disconnect connectors of all control modules 
communicating by means of CAN.
3) Check CAN communication circuit between control  modules for open, short and high resistance.
Is each CAN communication circuit in good condition? Go to Step 6. Repair circuit.
6 Keyless start control module power and ground circuit 
check
Check for keyless start control module power and ground 
circuit referring to “Keyless St art Control Module Power and 
Ground Circuit Check in Section 10E”.
Are they in good condition? Substitute a known-
good keyless start 
control module and 
recheck.
Repair keyless start 
control module power 
and/or ground circuits.
Step Action Yes No
Detecting Condition
Trouble Area
Communication error between ICM and ECM is detected 
by ECM. • Related fuse(s)
• Circuit between ICM and ECM
•ICM
•ECM
Step
Action YesNo
1 Was “Immobilizer Control S ystem Check” performed? Go to Step 2.Go to “Immobilizer 
Control System Check”.
2 Fuse check
1) Check fuse for ICM circuit.
Is fuse in good condition? Go to Step 3.
Replace fuse and check 
for short to power and 
ground circuit.
3 Voltage check at ICM power and ground terminal
1) Check power and ground terminal voltage of ICM 
connector referring to “Inspe ction of Immobilizer Control 
Module (ICM) and Its Circuit”.
Is each terminal voltage in good condition? Go to Step 4.
Repair circuit.  

Downloaded from www.Manualslib.com manuals search engine 10C-13 Immobilizer Control System: 
DTC P1622: EEPROM Reading / Writing ErrorS7RS0BA304013
Detecting Condition and Trouble Area
DTC Confirmation Procedure1) Turn ignition switch to ON position.
2) Check DTC in ECM.
Troubleshooting 1) Clear DTC(s) referring to “Diagnostic Trouble Code (DTC) Clearance”.
2) Turn the ignition switch to OFF position.
3) Check if DTC P1622 is still detected re ferring to “Diagnostic Trouble Code (DTC) Check”. If  still detected, go to the 
next step. If not, the troubleshooting is completed.
4) Replace ECM with new one referring to “ECM Removal and Installation in Section 1C”.
5) Perform “Procedure after ECM Replacement”.
DTC P1623: Unregistered TransponderS7RS0BA304014
Detecting Condition and Trouble Area
DTC Confirmation Procedure 1) Turn ignition switch to ON position.
2) Check DTC in ECM.
Troubleshooting 4
ICM and ECM connector check
1) With the ignition switch  at OFF position, check 
intermittent and poor connec tion of ICM connector and 
ECM connectors referring to “Intermittent and Poor 
Connection Inspection in Section 00”.
Is each connector in good condition? Go to Step 5. Repair poor connection.
5 Communication circuit check between ICM and ECM
1) Check for open, short and high resistance in serial 
communication and clock circuit between ICM and ECM.
Is each communication circuit in good condition? Substitute a known-
good ICM and recheck. 
If DTC P1621 is still 
detected, substitute a 
known good ECM and 
recheck.Repair circuit.
Step Action Yes No
Detecting Condition
Trouble Area
EEPROM in ECM is corrupted. ECM
Detecting Condition Trouble Area
Transponder code in the transponder built in the ignition 
key is invalid. • Use of unregistered ignition key
• Ignition key
•ICM
•ECM
Step
Action YesNo
1 Was “Immobilizer Control S ystem Check” performed? Go to Step 2.Go to “Immobilizer 
Control System Check”.
2 DTC check of ECM
Is DTC other than P1623 detected? Go to applicable DTC 
diag. flow.
Go to Step 3.  

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DTC P1625: Immobilizer Antenna ErrorS7RS0BA304015
Detecting Condition and Trouble Area
DTC Confirmation Procedure1) Turn ignition switch to ON position.
2) Check DTC in ECM.
Troubleshooting
DTC P1636: Immobilizer Information Registration FailureS7RS0BA304016
DTC Detecting Condition and Trouble Area
Troubleshooting 3
Registration of unregistered ignition key with ECM
1) Register unregistered igniti on key with ECM referring to 
“Registration of the Ignition Key”.
Was registration of ignition key completed? Unregistered ignition 
key.
Go to Step 4.
4 Registration of the spare ignition key
1) Register the spare ignition key referring to “Registration 
of the Ignition Key”.
Was registration of spare ignition key completed? Replace ignition key 
which cannot be 
registered.
Substitute a known-
good ECM and recheck.
Step Action Yes No
Detecting Condition
Trouble Area
ICM • ICM
•ECM
StepAction YesNo
1 Was “Immobilizer Control S ystem Check” performed? Go to Step 2.Go to “Immobilizer 
Control System Check”.
2 DTC confirmation
1) Clear DTC(s) referring to “Diagnostic Trouble Code 
(DTC) Clearance”.
2) Turn the ignition switch to OFF position.
3) Check ECM for DTC referring to “Diagnostic Trouble  Code (DTC) Check”.
Is DTC P1625 still detected? Replace ICM and 
recheck DTC. If DTC 
P1625 is still detected, 
substitute a known-
good ECM and recheck.
Intermittent trouble. 
Check for intermittent 
referring to “Intermittent 
and Poor Connection 
Inspection in Section 
00”.
Detecting Condition
Trouble Area
The registration  of the immobilizer control system 
information in ECM is failed. • CAN communication wire circuits
•BCM
•ECM
Step
Action YesNo
1 Was “Immobilizer Control S ystem Check” performed? Go to Step 2.Go to “Immobilizer 
Control System Check”.
2 DTC check of ECM
1) Check ECM for DTC referring to “DTC Check in Section 
1A”.
Is DTC P1674, P1675, P1678 and/or P1685 detected? Go to applicable DTC 
diag. flow.
Go to Step 3.  

Downloaded from www.Manualslib.com manuals search engine 10C-15 Immobilizer Control System: 
DTC P1638: Immobilizer Information MismatchedS7RS0BA304017
DTC Detecting Condition and Trouble Area
Troubleshooting3
DTC check of BCM
1) Check BCM for DTC referring to “DTC Check in Section 
10B”.
Is DTC U1073, U1100, and/or U1114 detected? Go to applicable DTC 
diag. flow.
Go to step 4.
4 CAN communication circuit check
1) Disconnect connectors from ECM, BCM and ABS 
control module.
2) Check CAN communication circuit for open, short and  high resistance.
• Between ECM and ABS control module
• Between BCM and ABS control module
Is each CAN communication circuit in good condition? Go to Step 5. Repair circuit.
5 Replacement of BCM
1) Replace BCM with new one referring to “BCM (Included 
in Junction Block Assembly)  Removal and Installation in 
Section 10B”.
2) Check ECM for DTC referring to “Diagnostic Trouble  Code (DTC) Check”.
Is DTC P1636 still detected? Substitute a known-
good ECM and recheck.
BCM faulty.
Step Action Yes No
Detecting Condition
Trouble Area
• The immobilizer control sys tem information in ECM and 
the one in BCM does not match.
• The registration of the  immobilizer control system 
information in ECM is failed. • Use of the wrong ECM
• CAN communication circuits
•BCM
•ECM
Step
Action YesNo
1 Was “Immobilizer Control S ystem Check” performed? Go to Step 2.Go to “Immobilizer 
Control System Check”.
2 DTC confirmation
1) Disconnect negative (–) cable from battery for more than 
5 seconds.
2) Connect negative (–) cable to battery.
3) Check if any DTC is detecte d referring to “Diagnostic 
Trouble Code (DTC) Check”.
Is DTC P1638 still detected? Go to Step 3.
Intermittent trouble. 
Check for intermittent 
referring to “Intermittent 
and Poor Connection 
Inspection in Section 
00”.
3 DTC check of ECM
1) Check ECM for DTC referring to “DTC Check in Section 
1A”.
Is DTC P1674, P1675, P1678 and/or P1685 detected? Go to applicable DTC 
diag. flow.
Go to Step 4.
4 DTC check of BCM
1) Check BCM for DTC referring to “DTC Check in Section 
10B”.
Is DTC U1073, U1100, U0155 and/or U1114 detected? Go to applicable DTC 
diag. flow.
Go to step 5.  

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Inspection of Immobilizer Control Module (ICM) and Its CircuitS7RS0BA304018
ICM and its circuit can be checked at ICM wiring connector by measuring voltage.
CAUTION! 
ICM cannot be checked by itself. It is strictly prohibited to connect voltmeter or ohmmeter to ICM with 
connector disconnected from it.
 
Voltage Check
1) Remove ICM (1) from steering lock assembly or steering lock unit referrin g to “Immobilizer Control Module (ICM) 
Removal and Installation”.
2) Connect ICM connector (2) to ICM.
3) Check voltage at each terminal.
NOTE
As each terminal voltage is affected by the battery voltage, confirm that it is 11 V or more when the 
ignition switch is turned to ON position.
 
5 CAN communication circuit check
1) Disconnect connectors from ECM, BCM and ABS 
control module.
2) Check CAN communication circuit for open, short and  high resistance.
• Between ECM and ABS control module
• Between BCM and ABS control module
Is each CAN communication circuit in good condition? Go to Step 6. Repair circuit.
6 Replacement of BCM
1) Replace BCM with new one referring to “BCM (Included 
in Junction Block Assembly)  Removal and Installation in 
Section 10B”.
2) Check ECM for DTC referring to “Diagnostic Trouble  Code (DTC) Check”.
Is DTC P1638 still detected? Substitute a known-
good ECM and recheck.
BCM faulty.
Step Action Yes No
12
3
4
G24
1
2
3
I4RS0BA30005-02
3. ICM connector (harness side view)