Immobilizer SUZUKI SWIFT 2007 2.G Service Service Manual
Page 1458 of 1496
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.  
Page 1459 of 1496
Downloaded from www.Manualslib.com manuals search engine Immobilizer Control System:  10C-16
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)  
Page 1460 of 1496
Downloaded from www.Manualslib.com manuals search engine 10C-17 Immobilizer Control System: 
Reference WaveformNOTE
When ECM cannot read the transponder code 
at the first try, ECM tries to read the 
transponder code repeatedly up to 8 times. 
The second waveform is the example 
showing that ECM read the transponder code 
successfully at the second try.
 
TerminalCircuit Normal Voltage Condition
G24-1 Power supply About 12.0 V
Ignition switch at ON position
0.0 V Ignition switch at OFF position
G24-2 Ground 0.0 V
Ignition switch at ON position
0.0 V Ignition switch at OFF position
G24-3 Serial communication line See the reference waveform.
—
0.0 V Ignition switch at OFF position
G24-4 Clock line See the reference waveform.
—
0.0 V Ignition switch at OFF position
[A]: The transponder code read successfully at the first try.
[B]: The transponder code read successfully at the second try.
1. Serial communication line
2. Clock line
3. First try
4. Second try
I4RS0AA30007-01
Measurement terminals CH1: G24-3 to G24-2 CH2: G24-4 to G24-2
Oscilloscope settings CH1: 5 V/DIV CH2: 5 V/DIV
TIME: 20 ms
Measurement condition Right after the ignition  switch is turned ON, the 
waveform can be read.  
Page 1461 of 1496
Downloaded from www.Manualslib.com manuals search engine Immobilizer Control System:  10C-18
Repair Instructions
Immobilizer Control Module (ICM) Removal and 
Installation
S7RS0BA306001
Removal1) Disconnect negative (–) cable at battery.
2) Remove steering wheel referring to “Steering Wheel  Removal and Installa tion in Section 6B”.
3) Remove steering column lower and upper covers.
4) Remove knee protector plate (1). (if equipped)
5) Remove engine start knob (2). (if equipped with  keyless start system)
6) Disconnect connector (1) from ICM (2).
7) Remove a screw (3) from ICM.
8) Remove ICM from steering lock assembly or  steering lock unit.
NOTE
The antenna part of ICM is fragile.
Therefore, do not add strong power to the 
part or twist the part.
 
Installation
Reverse the removal procedure.
Registration of the Ignition KeyS7RS0BA306002
To finish the registration  of the ignition key, the 
transponder code memorized in the transponder built in 
the ignition key has to be registered with ECM. To 
register the transponder code with ECM, perform 
“Register Ig Key” mode of SU ZUKI scan tool referring to 
“SUZUKI Tech 2 Operator’s Manual”.
NOTE
• A maximum of four transponder codes can  be registered with ECM.
• At an early part of the registration process,  all transponder codes of the ignition keys 
in use already registered with ECM are 
cleared. Therefore, before starting the 
registration, prepare all ignition keys in 
use in addition to the new ignition key(s) to 
be registered with ECM.
 
Procedure after ECM ReplacementS7RS0BA306003
After ECM is replaced with new one or used one, the 
transponder code in the transponder built in the ignition 
key has to be registered with ECM. To register 
transponder code in the ignition key with ECM, perform 
“Replace New ECM” mode of SUZUKI scan tool 
referring to “SUZUKI Tech 2 Operator’s Manual”.
NOTE
A maximum of four transponder codes can 
be registered with ECM.
 
2
1
I4RS0BA30006-03
2
3
1
I4RS0BA30007-03  
Page 1462 of 1496
Downloaded from www.Manualslib.com manuals search engine 10C-19 Immobilizer Control System: 
Special Tools and Equipment
Special ToolS7RS0BA308001
SUZUKI scan tool
—
This kit includes following 
items. 1. Tech 2, 2. PCMCIA 
card, 3. DLC cable, 4. SAE 
16/19 adapter, 5. Cigarette 
cable, 6. DLC loop back 
adapter, 7. Battery power 
cable, 8. RS232 cable, 9. 
RS232 adapter, 10. RS232 
loop back connector, 11. 
Storage case, 12. ) /  )  
Page 1465 of 1496
Downloaded from www.Manualslib.com manuals search engine Keyless Start System:  10E-3
Keyless Engine Start FunctionS7RS0BA501003
When the ignition knob switch (2) installed to the steering lock unit (1) is pushed, the keyless start control module (3) 
activates the center antenna (4) to send out the request signa l in the vehicle compartment. When the remote controller 
(5) receives the request signal from th e center antenna, it transmits the ID code to the keyless start control module. 
The keyless start control module compares the ID code sent  by the remote controller with the ID code registered in the 
keyless start control module. When these ID codes match,  the keyless start control module makes the key indicator 
lamp (7) in the combination meter (6) light  in blue and unlocks the steering lock unit to enable the ignition knob switch 
to turn. When the ignition knob switch is turned to ON posit ion in this state, ID codes of ECM and keyless start control 
module are compared through CA N communication (immobilizer function). Wh en they match, turning the ignition knob 
switch to start position will start the engine.
NOTE
When ignition knob switch is at ACC or ON position (engine not running) and any door has been kept 
open for a certain time, it may happen that engine fails to start. In such a case, turn ignition knob 
switch to OFF position once and then try to start engine again.
 
When the ID code from the remote controller and the ID code  registered in the keyless start control module do not 
match or when the remote controller is outside the operation  area of the remote controller and the ignition knob switch 
is pushed, the steering lock unit cannot be unlocked and so the ignition knob switch cannot be turned. Then, the 
keyless start control module makes the key indicator lamp in t he combination meter light in red to warn the driver that 
it is not possible to turn the  ignition knob switch. Also, when  the ID code of ECM and that of the keyless start control 
module do not match, the engine cannot  be started even if the ignition knob switch is turned to the start position. Then 
ECM makes the immobilizer light in the combination mete r flash to warn the driver that it is not possible to start the 
engine.
8 3
1
6 ii)
iii) iii)
iii)
iii)
iv)
i)
v)
vi)
vii)
7 6
2
[A]: i) ~ vii)
54
I5RS0CA50001-01
[A]: Signal flow
8. ECM  
Page 1470 of 1496
Downloaded from www.Manualslib.com manuals search engine 10E-8 Keyless Start System: 
Diagnostic Information and Procedures
Precautions in Diagnosing TroublesS7RS0BA504001
• The keyless start system executes data transmission/reception by means of th e radio wave. Therefore, 
proper operation may not be obtained if use of the 
door lock function and engine start function of the 
keyless start system is attempted near the place 
where strong radio wave is emitted (TV and radio 
broadcasting stations, etc.).
• Diagnostic information stored  in keyless start control 
module memory can be checked only by key indicator 
lamp.
• Be sure to use the trouble diagnosis procedure as  described in “Keyless Start  System Check”. Failure to 
follow it may result in incorrect diagnosis. (Some other 
DTC may be stored by mistake in the memory of 
keyless start control module during inspection.)
• Be sure to read “Precautions for Electrical Circuit  Service in Section 00” befo re inspection and observe 
what is written there.
• Communication of ECM, BCM, TCM (A/T model),  ABS control module, keyless start control module and 
combination meter is estab lished by CAN (Controller 
Area Network). (For detail of CAN communication for 
keyless start control module, refer to “CAN 
Communication System Description”). Therefore, 
handle CAN communication line with care referring to 
“Precaution for CAN Communication System in 
Section 00”. • Replacement of the keyless start control module
When keyless start control module is replaced with 
new one, make sure that r egister remote controller ID 
code to keyless start co ntrol module correctly 
according to “Registration Procedure for Remote 
Controller ID Code”.
• Keyless start control module substitution When the keyless start control module used in 
another vehicle was installed in the vehicle, register 
the ID code of the remote controller in the keyless 
start control module as well as the ignition key 
transponder code fo r the immobilizer control system in 
ECM. For the registration procedure of the ignition key 
transponder code, refer to “Registration of the Ignition 
Key in Section 10C”.
Self-Diagnosis FunctionS7RS0BA504002
The keyless start control module has self-diagnosis 
function to monitor the system components and circuits 
while the keyless start system is at work. When the 
keyless start control module detects an abnormality in 
the system, it saves the ar ea where such abnormality 
has occurred as a DTC in its memory. The DTC stored in 
memory of the keyless start control module is indicated 
by the key indicator lamp  in the combination meter 
flashing in a specific pattern. For DTC indication, refer to 
“DTC Check” and for the clearing procedure, to “DTC 
Clearance”.
Keyless Start System Diagnosis IntroductionS7RS0BA504003
To ensure that the trouble diagnosis is done accurately 
and smoothly, observe “Precautions in Diagnosing 
Troubles” and follow “Keyless Start System Check”.
Keyless Start System CheckS7RS0BA504004
Step Action YesNo
1 1) Record details of the problem. For your record, use of a  questionnaire form will facilit ate collecting information for 
proper analysis and diagnosis.
2) Check if the problem described in “Customer  Questionnaire (Example)” actually occurs in the vehicle. 
(This step should be performed with the customer if 
possible.)
Perform “Keyless Start System Operation Inspection” 
procedure to check if the symptom which has occurred is 
abnormal or not.
3) Check for DTC referring to “DTC Check”, and then  record DTC(s).
4) Clear DTC referring to “DTC Clearance” if any DTC  exists, and then recheck for DTC.
Is any DTC still detected? Go to Step 2.
Go to Step 3.
2 1) Check and repair referring to applicable “DTC Table”. Are check and repair complete? Go to Step 5.
Check and repair 
malfunction part(s), and 
go to Step 5.