Inspection of BCM SUZUKI SWIFT 2006 2.G Service Repair Manual
Page 1402 of 1496
Downloaded from www.Manualslib.com manuals search engine 10-ii Table of Contents
DTC P1615: ID Code Does Not Registered (Vehicle equipped with keyless start system 
only) ................................................................10C-9
DTC P1616: Different Registration ID Codes  (Vehicle equipped with keyless start system 
only) ..............................................................10C-10
DTC P1618: CAN Communication Error  (Reception Error for Keyless Start Control 
Module) (Vehicle equipped with keyless 
start system only) ..........................................10C-11
DTC P1621: Immobilizer Communication  Line Error ......................................................10C-12
DTC P1622: EEPROM Reading / Writing  Error ..............................................................10C-13
DTC P1623: Unregistered Transponder .........10C-13
DTC P1625: Immobilizer An tenna Error..........10C-14
DTC P1636: Immobilizer Information  Registration Failure .......................................10C-14
DTC P1638: Immobilizer Information  Mismatched ...................................................10C-15
Inspection of Immobilizer Control Module  (ICM) and Its Circuit ....... ...............................10C-16
Repair Instructions ........... ...............................10C-18
Immobilizer Control Mo dule (ICM) Removal 
and Installation ..............................................10C-18
Registration of the Ignition Key .......................10C-18
Procedure after ECM Replacement ................10C-18
Special Tools and Equipmen t .........................10C-19
Special Tool ....................................................10C-19
Keyless Start System ....... ......................10E-1
General Description ........................................... 10E-1
Keyless Start System Description ..................... 10E-1
Parts and Functions .......................................... 10E-2
Keyless Engine Start Function .......................... 10E-3
Door Lock Function of Keyless Start System .... 10E-4
Operation Area of Remote  Controller................ 10E-5
Alarm Function .................................................. 10E-6
CAN Communication System Description......... 10E-6
Schematic and Routing Diagram ...................... 10E-7 Keyless Start System El ectric Wiring Circuit 
Diagram .......................................................... 10E-7
Diagnostic Information and Procedures .......... 10E-8 Precautions in Diagnosing Troubles ................. 10E-8
Self-Diagnosis Function .................................... 10E-8
Keyless Start System Diagn osis Introduction ... 10E-8 Keyless Start System Chec
k ............................. 10E-8
Customer Questionnaire (E xample) .................. 10E-9
Key Indicator Lamp Check .............................. 10E-10
DTC Check...................................................... 10E-10
DTC Table ....................................................... 10E-11
DTC Clearance ............................................... 10E-12
Keyless Start System Symp tom Diagnosis ..... 10E-12
Keyless Start System Operation Inspection .... 10E-13
Door Lock Operation (Keyless Start System) . 10E-14
Inspection of Keyless Start Control Module  and Its Circuits .............................................. 10E-14
No DTC Detection After Performing DTC  Check ............................................................ 10E-18
Key Indicator Lamp Circuit Check (Key  indicator lamp doesn’t light when ignition 
knob switch is pushed.) ................................. 10E-20
Keyless Start Control Module Power and  Ground Circuit Check .................................... 10E-22
DTC No. 11: Communi cation Error with 
Steering Lock Unit ......................................... 10E-23
DTC No. 13 / No. 14: Release Signal Error  from Steering Lock Unit / Steering Lock Unit 
Malfunction .................................................... 10E-24
DTC No. 21 / No. 22: Internal Error of Keyless  Start Control Module  (EEPROM reading 
error) / (EEPROM writing error) ............ ........ 10E-24
DTC No. 31: Lost Commun ication with BCM .. 10E-25
DTC No. 33: Control Module Communication 
Bus Off .......................................................... 10E-27
DTC No. 51 / No. 52 / No. 53: Driver Side /  Passenger Side / Rear End Door Request 
Switch Failure................................................ 10E-28
Repair Instructions ............ .............................. 10E-30
Antennas and Request Switches Removal  and Installation .............................................. 10E-30
Front Door (Driver and Passenger Side), Rear  End Door Request Switch  Inspection............ 10E-31
Steering Lock Unit Removal and Installation .. 10E-31
Steering Lock Unit Inspection ......................... 10E-31
Front Door Lock Switch In spection ................. 10E-31
Keyless Start Control Module Removal and  Installation ..................................................... 10E-32
Remote Controller Inspection.......................... 10E-32
Replacement of Remote Controller Battery .... 10E-32
Registration Procedure  for Remote Controller 
ID Code ......................................................... 10E-33  
Page 1404 of 1496
Downloaded from www.Manualslib.com manuals search engine 10B-1 Body Electrical Control System: 
Control Systems
Body Electrical Control System
Precautions
Precautions in Diagnosing TroubleS7RS0BA200001
• Diagnostic information stored in BCM memory can be cleared as well as checked by using SUZUKI scan tool. 
Before using scan tool, read its Operator ’s (Instruction) Manual carefully to have good understanding as to what 
functions are available and how to use it.
• Be sure to read “Precautions for Electrical Circuit Serv ice in Section 00” before inspection and observe what is 
written there.
• Communication of ECM,  TCM (if equipped), ABS/ESP ® control module, steering angle sensor (ESP ® model), 
keyless start control module (if equipped), combinatio n meter and BCM is established by CAN (Controller Area 
Network). For detail of CAN communication for BCM,  refer to “CAN Communication System Description”. 
Therefore, handle CAN communication line with care referr ing to “Precaution for CAN Communication System in 
Section 00”.
General Description
BCM General DescriptionS7RS0BA201001
The Body electrical Control Module (BCM) is incorporated in junction block assembly. Do not attempt removal of BCM 
from junction block assembly as it may cause contact failure.
The BCM incorporates relays and controllers which are used for the following systems and controls them.
• Power door lock
• Keyless entry (if equipped)
• Door lock function of keyle ss start system (if equipped)
• Rear wiper
• Combination meter
• Interior light
• Warning buzzer
• Rear end door window defogger and door mirror heater (if equipped)
• Rear end door opener
• Theft deterrent light
Also, the BCM has a function to cause the interior light and open door warning lamp in the combination meter to turn 
off when any door is left open for longer than  15 minutes to reduce wasteful battery consumption.
In addition, it is possible to check operation of actuator whic h is controlled by BCM by using the output test function of 
SUZUKI scan tool to operate actuator simulatively.  
Page 1414 of 1496
Downloaded from www.Manualslib.com manuals search engine 10B-11 Body Electrical Control System: 
Customer Complaint Analysis
Record details of the problem (failure, complaint) and how it occurred as described by the customer.
For this purpose, use of such a questionnaire form as shown in figure will facilitate collectin g information to the point 
required for proper analysis and diagnosis. Customer questionnaire (example)
Problem Symptom Confirmation
Check if what the custom er claimed in “Customer 
Questionnaire” is accurately f ound in the vehicle. If that 
symptom is found, check whether the symptom is 
identified as a failure. (This step should be shared with 
the customer if possible.)
DTC Check
Check DTC stored in BCM me mory referring to “DTC 
Check”, record it and then clear it referring to “DTC 
Clearance”. DTC indicates malfunction that occurred in 
the system but does not indicate  whether it exists now or 
it occurred in the past and the normal condition has been 
restored now. To check which case applies, clear DTC 
once and check whether or not any fault exists.
Troubleshooting for DTC
Based on the DTC indicated in Step 3 and referring to 
applicable DTC flow, locate the cause of the trouble, 
namely in a sensor, wire harness, connector, BCM or 
other part and repair or replace faulty parts. Body Electrical Control System Symptom Diagnosis
Check the parts or system 
suspected as a possible 
cause referring to symptom diagnosis of each system.
Check for Intermi ttent Problem
Check parts where an intermit tent trouble is easy to 
occur (e.g., wire harness, connector, etc.), referring to 
“Intermittent and Poor Connec tion Inspection in Section 
00”.
Final Confirmation Test
Confirm that the problem symptom has gone and the 
body electrical control system is free from any abnormal 
conditions. If what has been repaired is related to the 
malfunction DTC, check DTC  again and confirm that no 
DTC is indicated.
Customers name: 
  Model: 
 VIN: 
 
Date of issue: 
  Date Reg: 
 Date of problem: 
  Mileage: 
 
Problem Symptoms
Power door lock system does not operate
Keyless entry system does not operate  
Rear end door window defogger does not operate
Rear wiper does not operate
Rear end door opener does not operate  
Other            
Frequency of Occurrence 
Continuous / Intermittent (       times a day, a month) 
/ Other          
 
Environmental Condition  
Weather:  
Fine / Cloudy / Rain / Snow / Other          
 
Temperature:    (F ) 
Diagnostic Trouble Code  Normal code / Malfunction code (           )
 
Warning buzzer does not sound
Interior light does not light
Theft deterrent light does not flush
I5RS0DA20006-01  
Page 1421 of 1496
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DTC B1141 / DTC B1142 (No. 1141 / No. 1142): Outside Air Temperature (Ambient Temp.) Sensor 
Circuit Malfunction
S7RS0BA204009
Wiring Diagram
DTC Detecting Condition and Possible Cause
Flow Test Description
Step 1: Check whether malfunction is in outside air temperature sensor.
Step 2: Check outside air temperature sensor input circuit.
Step 3: Check outside air temperature sensor ground circuit (for DTC B1141).
DTC Troubleshooting
I4RS0AA20010-01
[A]: BCM connector viewed from harness side 3. Junction block assembly
1. Outside air temperature sensor 4. Outside air temperature sensor connector
2. BCM
DTC detecting condition Possible cause
DTC B1141 (DTC No. 1141):
Input signal from outside air temperature sensor is higher 
than 4.88 V. • Open in outside air temperature sensor circuit
• Outside air temperature sensor malfunction
• BCM malfunction
DTC B1142 (DTC No. 1142):
Input signal from outside air temperature sensor is lower 
than 0.1 V. • Short in outside air temperature sensor circuit
• Outside air temperature sensor malfunction
• BCM malfunction
Step
Action YesNo
1 Check outside air temperature sensor
1) Turn ignition switch to OFF position.
2) Disconnect connector from outside air temperature 
sensor.
3) Check outside air temperature sensor for resistance  referring to “Outside Air Temperature Sensor Inspection 
(If Equipped) in Section 9C”.
Is it in good condition? Go to Step 2.
Replace outside air 
temperature sensor.  
Page 1426 of 1496
Downloaded from www.Manualslib.com manuals search engine 10B-23 Body Electrical Control System: 
DTC TroubleshootingStep Action YesNo
1 DTC check of BCM
Is DTC U0155 (No. 0155) and DTC U1073 (No. 1073) 
detected together? Go to “DTC U1073 (No. 
1073): Control Module 
Communication Bus 
Off”.Go to Step 2.
2 Control module connector check
1) Check connection of connectors of all control modules 
communicating by means of CAN.
2) Recheck BCM for DTC.
Is DTC U0155 (No. 0155) detected? Go to Step 3.
Intermittent trouble.
Check for intermittent 
referring to “Intermittent 
and Poor Connection 
Inspection in Section 
00”.
3 Combination meter power and ground circuit check
1) Turn ignition switch to ON position.
Do warning lights in combi nation meter other than key 
indicator light light up? Go to Step 4.
Check combination 
meter power and 
ground circuit. If circuit 
is OK, substitute a 
known-good 
combination meter and 
recheck.
4 CAN communication circuit check
1) Turn ignition switch to OFF position.
2) Disconnect connectors from BCM, combination meter 
and steering angle sensor (ESP ® model).
3) Check CAN communication circuit between BCM and  combination meter for open, short and high resistance.
Is each CAN communication circuit in good condition? Go to Step 5.
Repair circuit.
5 CAN communication circuit check
1) Disconnect connectors of all control modules 
communicating by means of CAN.
2) Check CAN communication circuit between control  modules other than Step 4 for open, short and high 
resistance.
Is each CAN communication circuit in good condition? Go to Step 6.
Repair circuit.
6 DTC check of BCM
1) Connect connectors of disconnected control modules 
communicating by means of CAN.
2) Disconnect connector of any one of control module other  than BCM.
3) Recheck BCM for DTC.
Is DTC U0155 (No.0155) detected? Disconnect connectors 
of control modules other 
than the one whose 
connector is 
disconnected in Step 2) 
one by one and check 
that DTC U0155 is 
detected by BCM each 
time connector is 
disconnected. When 
DTC U0155 is not 
detected by BCM while 
checking in this way, go 
to description under 
“NO” below. If DTC 
U0155 is detected by 
BCM even when 
connectors of all control 
modules that use CAN 
communication with 
BCM are disconnected, 
substitute a known-
good BCM and recheck.Check power and 
ground circuit of control 
module disconnected in 
Step 2). If circuit is OK, 
substitute a known-
good control module 
disconnected in Step 2) 
and recheck.  
Page 1427 of 1496
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DTC U1073 (No. 1073): Control Module Communication Bus OffS7RS0BA204014
Wiring Diagram
Refer to “DTC U0155 (No. 0155): Lost Communication with Instrument Panel Cluster (IPC) Control Module”.
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure 1) Connect scan tool to DLC with  ignition switch turned OFF.
2) Turn ON ignition switch and clear DTC by using scan tool.
3) Start engine and run it for 1 min. or more.
4) Check DTC.
DTC Troubleshooting DTC detecting condition Trouble area
Transmission error that is inconsistent between transmission data and 
transmission monitor (CAN bus monitor)  data is detected more than 7 
times continuously.
(1 driving detection logic) • CAN communication circuit
• Combination meter
• BCM (included in junction block 
assembly)
• TCM (A/T model)
• ABS/ESP ® control module
• Keyless start control module (if equipped)
•ECM
• Steering angle sensor (if equipped)
Step Action YesNo
1 Control module connector check
1) Check connection of connectors of all control modules 
communicating by means of CAN.
2) Recheck DTC.
Is DTC U1073 detected? Go to Step 2.
Intermittent trouble. 
Check for intermittent 
referring to “Intermittent 
and Poor Connection 
Inspection in Section 
00”.
2 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 3.
Repair circuit.  
Page 1429 of 1496
Downloaded from www.Manualslib.com manuals search engine Body Electrical Control System:  10B-26
DTC TroubleshootingStep Action Yes No 1 DTC check of BCM
Is DTC U1100 (No. 1100) and DTC U1073 (No. 1073) 
detected together? Go to “DTC U1073 (No. 
1073): Control Module 
Communication Bus 
Off”.Go to Step 2.
2 DTC check of ECM
1) Check ECM for DTC.
Is DTC P1674 detected? Go to “DTC P1674: 
CAN Communication 
(Bus Off Error) in 
Section 1A”.Go to Step 3.
3 DTC check of ABS/ESP ® control module
1) Check ABS/ESP ® control module for DTC.
Is DTC U1073 detected? Go to “DTC U1073: 
Control Module 
Communication Bus Off 
in Section 4E” or “DTC 
U1073: Control Module 
Communication Bus Off 
in Section 4F”.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 BCM for DTC.
Is DTC U1100 (No. 1100) detected? Go to Step 5. Intermittent trouble. 
Check for intermittent 
referring to “Intermittent 
and Poor Connection 
Inspection in Section 
00”.
5 DTC check of ABS/ESP ® control module
1) Check DTC for ABS/ESP ® control module.
Is DTC U1100 detected? Go to Step 6. Go to Step 7.
6 CAN communication circuit check
1) Disconnect connector s from ECM and ABS/ESP ® 
control module.
2) Check CAN communication circuit between ECM and  ABS/ESP ® control module for open, short and high 
resistance.
Is each CAN communication circuit in good condition? Check ECM power and 
ground circuit. If circuit 
is OK, substitute a 
known-good ECM and 
recheck.
Repair circuit.
7 CAN communication circuit check
1) Disconnect connector s from BCM and ABS/ESP ® 
control module.
2) Check CAN communication circuit between BCM and  ABS/ESP ® control module for open, short and high 
resistance.
Is each CAN communication circuit in good condition? Go to Step 8. Repair circuit.
8 CAN communication circuit check
1) Disconnect connectors of all control modules 
communicating by means of CAN.
2) Check CAN communication circuit between control  modules other than Step 7 for open, short and high 
resistance.
Is each CAN communication circuit in good condition? Go to Step 9. Repair circuit.  
Page 1431 of 1496
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4Control module connector check
1) Check connection of connectors of all control modules 
communicating by means of CAN.
2) Recheck BCM for DTC.
Is DTC U1101 (No. 1101) detected? Go to Step 5. Intermittent trouble. 
Check for intermittent 
referring to “Intermittent 
and Poor Connection 
Inspection in Section 
00”.
5 DTC check of ECM
1) Check ECM for DTC.
Is DTC P1676 detected? Go to Step 6. Go to Step 7.
6 CAN communication circuit check
1) Disconnect connectors from ECM and TCM.
2) Check CAN communication circuit between ECM and 
TCM for open, short and high resistance.
Is each CAN communication circuit in good condition? Check TCM power and 
ground circuit. If circuit 
is OK, substitute a 
known-good TCM and 
recheck.
Repair circuit.
7 CAN communication circuit check
1) Disconnect connectors from  BCM, ABS control module 
and ECM.
2) Check CAN communication circuit between BCM and  ECM for open, short and high resistance.
• Between BCM and ABS control module
• Between ECM and ABS control module
Is each CAN communication circuit in good condition? Go to Step 8. Repair circuit.
8 CAN communication circuit check
1) Disconnect connectors of all control modules 
communicating by means of CAN.
2) Check CAN communication circuit between control  modules other than Step 7 for open, short and high 
resistance.
Is each CAN communication circuit in good condition? Go to Step 9. Repair circuit.
9 DTC check of BCM
1) Connect connectors of disconnected control modules 
communicating by means of CAN.
2) Disconnect connector of any one of control module other  than BCM.
3) Recheck BCM for DTC.
Is DTC U1101 (No.1101) detected? Disconnect connectors 
of control modules other 
than the one whose 
connector is 
disconnected in Step 2) 
one by one and check 
that DTC U1101 is 
detected by BCM each 
time connector is 
disconnected. When 
DTC U1101 is not 
detected by BCM while 
checking in this way, go 
to description under 
“NO” below. If DTC 
U1101 is detected by 
BCM even when 
connectors of all control 
modules that use CAN 
communication with 
BCM are disconnected, 
substitute a known-
good BCM and recheck.Check power and 
ground circuit of control 
module disconnected in 
Step 2). If circuit is OK, 
substitute a known-
good control module 
disconnected in Step 2) 
and recheck.
Step Action Yes No  
Page 1432 of 1496
Downloaded from www.Manualslib.com manuals search engine 10B-29 Body Electrical Control System: 
DTC U1144 (No. 1144): Lost Communication with Keyless Start Control ModuleS7RS0BA204017
Wiring Diagram
Refer to “DTC U0155 (No. 0155): Lost Communication with Instrument Panel Cluster (IPC) Control Module”.
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure 1) Connect scan tool to DLC with  ignition switch turned OFF.
2) Turn ON ignition switch and clear DTC by using scan tool.
3) Start engine and run it for 1 min. or more.
4) Check DTC.
DTC Troubleshooting DTC detecting condition Trouble area
BCM can not receive data sent by CAN from keyless start control module for 
longer than specified time continuously. • CAN communication circuit
• Combination meter
• Keyless start control module
• BCM (included in junction block 
assembly)
Step Action YesNo
1 DTC check of BCM
Is DTC U1144 (No. 1144) and DTC U1073 (No. 1073) 
detected together? Go to “DTC U1073 (No. 
1073): Control Module 
Communication Bus 
Off”.Go to Step 2.
2 DTC check of keyless start control module
1) Check keyless start co ntrol module for DTC.
Is DTC No. 33 detected? Go to “DTC No. 33: 
Control Module 
Communication Bus Off 
in Section 10E”.Go to Step 3.
3 Control module connector check
1) Check connection of connectors of all control modules 
communicating by means of CAN.
2) Recheck BCM for DTC.
Is DTC U1144 (No. 1144) detected? Go to Step 4.
Intermittent trouble. 
Check for intermittent 
referring to “Intermittent 
and Poor Connection 
Inspection in Section 
00”.
4 CAN communication circuit check
1) Disconnect connectors from BCM, combination meter 
and keyless start control module.
2) Check CAN communication circuit for open, short and  high resistance.
• Between BCM and combination meter
• Between combination meter and keyless start control module
Is each CAN communication circuit in good condition? Go to Step 5.
Repair circuit.
5 CAN communication circuit check
1) Disconnect connectors of all control modules 
communicating by means of CAN.
2) Check CAN communication circuit between control  modules other than Step 4 for open, short and high 
resistance.
Is each CAN communication circuit in good condition? Go to Step 6.
Repair circuit.  
Page 1434 of 1496
Downloaded from www.Manualslib.com manuals search engine 10B-31 Body Electrical Control System: 
Inspection of BCM and its CircuitsS7RS0BA204018
BCM and its circuits can be checked at BCM wiring couplers by measuring voltage and resistance.
CAUTION! 
BCM cannot be checked by itself. It is strictly prohibited to connect voltmeter or ohmmeter to BCM 
with couplers disconnected from it.
 
Voltage Check1) Disconnect negative (–) cable at battery.
2) Remove BCM (included in junction block assembly) refe rring to “BCM (Included in Junction Block Assembly) 
Removal and Installation”.
3) Connect connectors to BCM (1) and junction block assembly (2).
4) Check voltage at each terminal number of couplers connected. For connector and terminal number, refer to “Connector  Layout Diagram of BCM and Junction Block Assembly”.
NOTE
• As each terminal voltage is affected by the battery voltage, confirm that it is 11 V or more when 
ignition switch is ON.
• Voltage with asterisk (*) can not be measured by voltmeter because it is pulse signal. Check it with oscilloscope if necessary.
 
BCM connector “L01”
1
2
1
2
I4RS0AA20030-01
Terminal CircuitNormal voltage Condition
L01-1 Passenger side door lock 
actuator control 
(Unlock) (if equipped) 10 – 14 V
Unlock signal is output fo
r passenger side door lock 
actuator
0 V Unlock signal is not output for passenger side door lock 
actuator
L01-2 — — —
L01-3 Rear end door switch 10 – 14 V Rear end door is closed
0 V Rear end door is opened
L01-4 Rear end door opener switch 10 – 14 V Rear end door switch is not pushed
0 V Rear end door switch is pushed
L01-5 Manual door lock switch
(Unlock) 10 – 14 V
Manual door lock switch is at any position other than 
unlock position
0 V Manual door lock switch is at unlock position
L01-6 Parking brake switch *0 – 3 V
↑↓
10 – 14 V Refer to “Reference waveform No. 1: ”
0 V Ignition switch is at ON po
sition and parking brake lever 
is pulled up
L01-7 Driver side door switch 10 – 14 V Driver side door is closed
0 V Driver side door is opened