2008 SUZUKI SWIFT Junction block

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.

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

Downloaded from www.Manualslib.com manuals search engine Body Electrical Control System: 10B-34
Junction block connector “E40”
Junction block connector “E41”
Junction block connector “G32”
Junction block connector “G33”
Junction block connector “G34”
Junction block connector “K01”
Junction block connector “L04”
Junction block connector “L05”Terminal Circuit Normal voltage Condition
E40-2 Backup power source 10 – 14 V Igni tion switch is at all positions
TerminalCircuitNormal voltage Condition
E41-3 Horn 10 – 14 V Horn switch is at ON position
0 V Horn switch is at OFF position
Terminal CircuitNormal voltage Condition
G32-2 Power source (IG) 10 – 14 V Ignition switch is at ON position
0 V Ignition switch is at any position other than ON position
G32-5 Power source (ACC) 10 – 14 V Ignition switch is at ACC or ON position
0 V Ignition switch is at any position other than ACC or ON
position
Terminal
CircuitNormal voltage Condition
G33-3 Ground for BCM 0 V Ignition switch is at all positions
G33-7 Rear end door window
defogger indicator light 10 – 14 V
Engine is running and rear end door window defogger
indicator light is lit up
0 V Engine is running and rear end door window defogger
indicator light is not lit up
Terminal
CircuitNormal voltage Condition
G34-3 Horn switch 10 – 14 V Horn switch is not pushed
0 V Horn switch is pushed
G34-7 Lighting switch 10 – 14 VEngine is running (equipped with DRL) or lighting
switch is at any position other than OFF position
0 V Lighting switch is at OFF position
G34-9 Ground for BCM 0 V Ignition switch is at all positions
G34-11 Hazard warning switch 0 VHazard warning switch is at
ON position or lock or
unlock button of key less entry transmitter (answer
back control) is pushed
10 – 14 V Hazard warning switch is at OFF position
Terminal CircuitNormal voltage Condition
K01-5 Interior light 10 – 14 V
Interior light switch is at
DOOR position and interior
light is not lit up
0 V Interior light switch is at
DOOR position and interior
light is lit up
Terminal CircuitNormal voltage Condition
L04-2 Air bag communication line *0 – 1 V
↑↓
4 – 6 V Refer to “Reference
waveform No. 13: ”
L04-3 Serial communication line of
data link connector for SDM 8 – 12 V Ignition switch is at ON position
Terminal
CircuitNormal voltage Condition
L05-4 Ground for BCM 0 V Ignition switch is at all positions
L05-5 Power supply for rear wiper
motor 10 – 14 V Ignition switch is at ON position

Downloaded from www.Manualslib.com manuals search engine 10B-35 Body Electrical Control System:
Junction block connector “L06”
Reference waveform No. 1
Parking brake or brake fluid level switch signal (1)Reference waveform No. 2
“3” position switch signal (1) for TCM
L05-6
Right side door mirror heater
(if equipped) 10 – 14 V
Engine is running and rear end door window defogger
is in operation
0 V Engine is running and rear end door window defogger
is not in operation
L05-7 Left side door mirror heater (if
equipped) 10 – 14 V
Engine is running and rear end door window defogger
is in operation
0 V Engine is running and rear end door window defogger
is not in operation
L05-8 Rear end door window
defogger wire 10 – 14 V
Engine is running and rear end door window defogger
is in operation
0 V Engine is running and rear end door window defogger
is not in operation
L05-9 Rear wiper control 10 – 14 V
Ignition switch is at ON posi
tion and rear wiper is not in
operation
0 V Ignition switch is at ON pos
ition and rear wiper is in
operation
Terminal Circuit Normal voltage Condition
Terminal
CircuitNormal voltage Condition
L06-9 Door lock actuator control
(Unlock) 10 – 14 V Unlock signal is outpu
t for rear door lock actuator
0 V Unlock signal is not output for rear door lock actuator
L06-10 Door lock actuator control
(Lock) 10 – 14 V Lock signal is output for all door lock actuators
0 V Lock signal is not output for all door lock actuators
Measurement terminal Parking brake switch
CH2: “L01-6” to “G33-3”
Brake fluid level switch
CH2: “E46-5” to “G33-3”
Oscilloscope setting CH2: 5 V / DIV
TIME: 10 ms / DIV
Measurement
condition Parking brake switch:
• Ignition switch is at ON
position, parking brake lever
is released
Brake fluid level switch
• Ignition switch is at ON position, brake fluid level is in
normal
I4RS0AA20018-02
Measurement terminal CH2: “L01-8” to “G33-3”
Oscilloscope setting CH2: 5 V/DIV
TIME: 4 ms/DIV
Measurement
condition Ignition switch is at ON position
and A/T selector lever is at any
position other than “2” or “3”
position
I4RS0AA20015-02

Downloaded from www.Manualslib.com manuals search engine 10B-39 Body Electrical Control System:
Repair Instructions
BCM (Included in Junction Block Assembly)
Removal and Installation
S7RS0BA206001
CAUTION!
Do not attempt removal of BCM from junction
block assembly as it may cause contact
failure.
If there is faulty condition in BCM, replace
junction block assembly.

Removal
1) Disconnect negative (–) cable from battery.
2) Disable air bag system referring to “Disabling Air Bag System in Section 8B”.
3) Remove dash side trim (1) and steering column hole cover (2).
4) Remove junction block assembly mounting nuts (3).
5) Disconnect connectors from BCM and junction block assembly.
6) Detach wiring harness clamp from junction block assembly.
Installation
Reverse removal procedure for installation, noting
following points.
• Connect connectors securely.
• Enable air bag system referring to “Enabling Air Bag System in Section 8B”.
Outside Air Temperature Sensor Removal and
Installation
S7RS0BA206002
For removal and installation, refer to “Outside Air
Temperature Sensor Removal and Installation (If
Equipped) in Section 9C”.
Outside Air Temperature Sensor InspectionS7RS0BA206003
For inspection, refer to “Outside Air Temperature Sensor
Inspection (If Equipped) in Section 9C”.
Security Alarm Mode Selection Procedure (If
Equipped)
S7RS0BA206004
Security alarm mode can be selected by performing the
following procedure.
1) Confirm that all doors are closed, all doors are unlocked and ignition key is inserted in ignition key
cylinder.
2) Remove ignition key from ignition key cylinder.
3) Perform Step a) through e) described below within 15 seconds.
a) Insert ignition key (1) in ignition key cylinder (2).
b) Remove ignition key from ignition key cylinder.
c) Repeat Step a) and b) twice.
d) Insert ignition key in ignition key cylinder.
e) Push lock side (3) of driver side manual lock switch (4) 3 times.
4) When Step 3) is completed, the mode changes to the next one automatically. The warning buzzer
(located in BCM) sounds by the number of specified
for each mode as follows.
• Changed from A mode to B mode: Buzzer sounds 4 times
• Changed from B mode to A mode: Buzzer sounds once
4. BCM 5. Junction block assembly
I4RS0BA20010-01
4
3
1
2
I5RS0DA20007-01

Downloaded from www.Manualslib.com manuals search engine Immobilizer Control System: 10C-4
Schematic and Routing Diagram
Immobilizer Control System Wiring Circuit DiagramS7RS0BA302001
NOTE
For more details about power supply and ground circuits for ECM, BCM, keyless start control module,
ABS control module and combination meter, refer to “System Ci rcuit Diagram in Section 9A”.

BLK/WHT
BLK/ORN12V
G24-1
G24-2
12V
5V
12V
12VYEL/RED
YEL/BLK
G24-4
G24-3
12V
5V
BRN
BRN/YEL
BLK/YEL
1
2
2 2
2
34
2 6712
11
9
14
12
3
4
G24
[A]
5
6
REDWHT
G42-20 G42-29 G42-30
G04-3 G04-7 G04-8
WHT/RED
5V
5V
5
G28-9 G28-7
G42-18G42-19
E23-13
E23-28
IG1
PPL/WHT 10
PPL/WHT
PPL/WHT
E23-5
RED
WHT**E85-46E23-18
E23-3
RED
WHT
E46-1
E46-2
WHT
RED
G37-2
G37-4
WHT/BLK
RED/BLK
G37-1
G37-3
12V
E46-9
G37-5
13
8
**E85-42
**E85-13
**E85-44
G28-10
G28-8
*E03-8 *E03-10
*E03-12
*E03-6
I7RS0BA30001-01
[A]: Immobilizer control module connector (harness side vi ew) 6. Immobilizer control module (ICM) 12. Steering lock unit
1. Battery 7. ECM 13. ABS/ESP ® control module
2. Fuse 8. BCM 14. CAN junction connector (ESP ® model)
3. Ignition switch 9. Combination meter *: ABS model
4. Junction block assembly 10. Immobilizer indicator lamp **: ESP ® model
5. Data link connector (DLC) 11. Keyless start control module

Downloaded from www.Manualslib.com manuals search engine Immobilizer Control System: 10C-8
Immobilizer Indicator Lamp Remains ON after Engine StartsS7RS0BA304007
Wiring Diagram
Refer to “Immobilizer Control S ystem Wiring Circuit Diagram”.
Circuit Description
When the ignition switch is turned ON, ECM read the code by the coil antenna from ignition key. Then if the code in
transponder in the key match with the one registered with ECM, transmits indication ON signal of immobilizer indicator
lamp to combination meter in order to turn immobilizer indicator lamp on. And then, combination meter turns
immobilizer indicator lamp on. When th e engine starts to run and no malfunction is detected in the system, ECM
transmits immobilizer indicator lamp indication O FF signal to combination meter in order to turn immobilizer indicator
lamp off. And then, comb ination meter turns immobilizer indicator lamp off, but if a malfunction was or is detected,
immobilizer indicator lamp is flashes ON and OF F, when ignition switch turn to ON position.
Troubleshooting 4
Fuse check
1) Turn ignition switch to OFF position.
2) Check for fuse blown at combination meter circuit fuse in
junction block assembly.
Is fuse in good condition? Go to Step 5. Replace fuse and check
for short to power or
ground 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 for open, short and high resistance.
Is each CAN communication circuit in good condition? Go to Step 6. Repair circuit.
6 Combination meter power and ground circuit check
1) Remove combination meter referring to “Combination
Meter Removal and Installation in Section 9C”.
2) Check for proper connection to combination meter connector terminals.
3) If OK, then turn ignition switch to ON position, Check terminal voltage of combination meter between power
supply and ground terminal. Refer to “Combination
Meter Circuit Diagram in Section 9C”.
Is it 10 – 14 V? Substitute a known-
good combination meter
and recheck. If
immobilizer indicator
lamp still remains OFF,
substitute a known good
ECM and recheck.
Repair power supply
and/or ground circuit.
Step Action Yes No
Step
Action YesNo
1 DTC check of ECM
1) Start engine and recheck DTC of ECM while engine
running.
Is DTC P1674, P1675, P1678 and/or P1685 detected? Go to applicable DTC
diag. flow.
Go to Step 2.
2 CAN communication circuit check
1) Disconnect connectors from ECM, BCM, ABS control
module and combination meter.
2) Check CAN communication circuit for open, short and high resistance.
• Between ECM and ABS control module
• Between BCM and ABS control module
• Between BCM and combination meter
Is each CAN communication circuit in good condition? Substitute a known-
good combination meter
and recheck. If
immobilizer indicator
lamp still remains ON,
substitute a known-
good ECM and recheck.
Repair circuit.

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.