Can SUZUKI SWIFT 2005 2.G Service Workshop Manual
Page 1405 of 1496
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CAN Communication System DescriptionS7RS0BA201002
Refer to “CAN Communication System Description in Section 1A” for CAN communication system description. BCM 
communication control data with ea ch control module as follows.
BCM Transmission Data
BCM Reception Data
A/C switch ON signal
Electric load signal
"3" position switch signal
Illumination ON signal
Brake fluid level switch signal
Parking brake switch signal
Seat belt buckle switch signal
Charging system signal
Engine oil pressure switch signal
Diagnostic trouble code (DTC)
Door switch status
Door lock status ECM
TCM
(A/T model) Combination 
Meter  Keyless Start
Control Module
(if equipped)
Transmit DATA
BCM
ESP
Control Module
(if equipped)
I7RS0BA20002-01
Engine speed signal
Vehicle speed signal Engine coolant temperature signal
A/C refrigerant pressure signal
Fuel consumption signal A/C compressor clutch signal
Transmission range sensor signal
Fuel level signal
Ignition knob switch signal
Door lock/unlock request signal
Buzzer request signal
Answer back request signal
DATA
BCM
Receive
Combination
Meter
TCM
(A/T model) Keyless Start
Control Module (if equipped)
ECM
I7RS0AA20001-01  
Page 1406 of 1496
Downloaded from www.Manualslib.com manuals search engine 10B-3 Body Electrical Control System: 
Theft Deterrent LightS7RS0BA201003
The information display or clock (1) of this vehicle includes a theft deterrent light (2) for the theft preventive purpose. 
The BCM makes the theft deterrent light flash at certain interval s after the ignition switch is turned off until it is turned 
on again. Also, to check DTCs stored in BCM without usin g a SUZUKI scan tool when diagnosing troubles, it is 
possible to identify them by flashing  patterns of the theft deterrent light.
Security Alarm Description (If Equipped)S7RS0BA201004
Operation
The security alarm system provides a warning of an abnormal  condition to those who are around. Its operation is as 
follows. While the system is in the stand- by mode (when 20 seconds or more elapsed after the door is locked using a 
keyless entry transmitter or door request switch), BCM monitors  door lock status, door switch status and battery power 
supply voltage. When it detects an abnormal condition (door  is unlocked by some way other than using keyless entry 
transmitter or door request switch and opened or cut off BCM power supply voltage temporarily), it activates the 
warning buzzer (located in BCM), theft deterr ent light, hazard warning relay and horn relay.
The security alarm system  has 2 selectable modes.
• A mode: No operation
• B mode: Theft deterrent light blinks, hazard warning lights  blink, warning buzzer (located in BCM) sounds and horn 
sounds
When B mode is selected and the door is locked using keyl ess entry transmitter or door request switch, the theft 
deterrent light (1) flashes at  0.1 second interval for 20 seconds and the se curity alarm system is set to the stand-by 
mode (2). Once it is se t to the stand-by mode, the theft deterrent light blinks at 2 second intervals.
When the system is set to stand-by mode and the door is  unlocked by some way other than using keyless entry 
transmitter or door request switch and opened or cut off BCM power supply voltage temporarily, the alarm devices 
operate according to the selected mode as described above.
The alarm stops under either of the following conditions.
• Ignition switch is turned ON
• A certain time has elapsed since the alarm started
For selection of the mode of the security alarm system , refer to “Security Alarm Mode Selection Procedure (If 
Equipped)”.
1 2I4RS0AA20031-01
B A1T3
T1
T2 2
C
I5RS0DA20003-01
A: Indicator lamp turned ON
T1: 0.1 seconds
B: Indicator lamp turned OFF T2: 20 seconds
C: When door is locked using keyless entry tr ansmitter or door request switch T3: 2 seconds  
Page 1409 of 1496
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[A]: Vehicle not equipped with diagnosis connector 19. Door key cylinder switch (included in door lock actuator)40. SDM
[B]: Vehicle equipped with diagnosis conn ector 20. Manual door lock switch 41. Rear end door window defogger relay
[C]: ESP ® model 21. Rear end door window defogger switch 42. Rear end door window defogger
1. BCM (included in junction block assembly) 22. Rear end door opener switch 43. Rear end door window defogger indicator lamp
2. Rear washer motor 23. “3” position switch (A/T model)44. Horn relay
3. Rear wiper motor 24. A/C switch45. Horn switch
4. Rear wiper relay 25. Rear end door opener relay46. Horn
5. Rear wiper and washer switch 26. Rear end door opener actuator47. Lighting switch
6. Outside air temperature sensor 27. TCM (A/T model)48. Ignition switch
7. Key reminder switch 28. ECM49. Battery
8. Theft deterrent light 29. Combination meter50. To turn signal light
9. Oil pressure switch 30. Data link connector (DLC)51. Body ground
10. Generator 31. To ECM, ABS/ESP®, P/S control module 52. Engine ground
11. Information display (if equipped) 32. To SDM53. Keyless start control module (if equipped)
12. Keyless entry receiver (if equipped) 33. Door lock actuator relay 54. Right side door mirror heater (if equipped)
13. Driver side door switch 34. Driver side door lock actuator55. Left side door mirror heater (if equipped)
14. Other than driver side door switch 35. Passenger side door lock actuator56. ABS/ESP® control module
15. Rear end door switch 36. Rear door lock actuator57. To HVAC control module
16. Driver side seat belt switch 37. Turn signal and hazard warning relay 58. CAN junction connector
17. Brake fluid level switch 38. Hazard warning switch59. Steering angle sensor
18. Parking brake switch 39. Interior light  
Page 1412 of 1496
Downloaded from www.Manualslib.com manuals search engine 10B-9 Body Electrical Control System: 
Diagnostic Information and Procedures
BCM Self-Diagnosis FunctionS7RS0BA204001
• BCM monitors conditions of the system components and its circuit with ignition switch turned to ON position. When 
an abnormality in the system oc curs, the area where that abnormality lies is stored in the memory of EEPROM in 
BCM.
• DTC can be checked in either one of following ways. – DTC can be checked by SUZUKI scan tool (2) connected to DLC (1).
– DTC can be read from flashing pattern  of theft deterrent light (3). Also, DTC is displayed on combination meter 
(4) at the same time.
BCM input / output table
4. Oil pressure switch 15. Rear end door window defogger switch 26. Rear wiper relay
5. Outside air temperature sensor (if  equipped) 16. A/C switch
27. Rear end door window defogger relay
6. Door lock actuator  (incorporated in key cylinder switch) 17. Hazard warning switch
28. Turn signal and hazard warning relay
7. Door switch 18. Rear wiper switch 29.  Key reminder switch (included in ignition switch)
8. Interior light 19. Lighting switch
9. Rear end door opener switch 20. Manual door lock switch
3
1
2
4I4RS0BA20004-03
Control
Input Output
Power door lock system • Key cylinder switch
• Manual door lock switch • Each door lock actuator
Keyless entry system • Key reminder switch
• Keyless entry receiver
• Driver side door switch • Each door lock actuator
• Turn signal and hazard warning relay
• Interior light
Keyless start system
(Door lock function) • Keyless start control module
• Each door lock actuator
• Turn signal and hazard warning relay
• Interior light
Rear wiper  • Rear wiper INT switch
• Rear wiper LO switch • Rear wiper relay
Combination meter • Tail light switch
• Oil pressure switch
• Parking brake switch
• Driver side seat belt switch
• Brake fluid level switch
• Generator
• Each door switch • Combination meter  
Page 1415 of 1496
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Scan Tool DataS7RS0BA204003
Scan tool DataConditionNormal condition / 
reference value
Vehicle Speed At stop with ignition switch turned ON 0 km/h
Outside air Temp Reference value is relative to outside air temperature –40 
°C – 70  °C
(–40  °F – 158 ° F)
Battery Voltage At specified idle speed after warming up 10 – 14 V
Coolant Temp At specified idle speed after warming up 80 
°C – 100 ° C
(176  °F – 212 ° F)
Engine Speed Engine idling with no load applied after warming up Desired idle speed
± 50 rpm
Fuel Consumption At specified idle speed after warming up 0.0 km/l
Key Reminder Sw Ignition key inserted in 
ignition key cylinder Key in
Ignition key pulled out from ignition key cylinder Pulled
Rear Wiper Sw Rear wiper switch at ON position and ignition switch turned ON
ON
Rear wiper switch at INT position  and ignition switch turned ON INT
Rear wiper switch at OFF position and ignition switch turned ON OFF
Door key Sw  Key cylinder switch of driver side door at lock position
LOCK
Key cylinder switch of driver side door not turned Neutral
Key cylinder switch of driver side  door at unlock position Unlock
Door Lock Sw Lock side of manual door lock switch pressed
LOCK
Manual door lock switch not pressed Neutral
Unlock side of manual door lock switch pressed Unlock
Driv Door Sw  Driver side door open
Open
Driver side door closed Close
Pass Door Sw Doors other than driver side door open
Open
Doors other than driver side door closed Close
Brake Fluid Level Brake fluid level at MIN level or higher
Normal
Brake fluid level lower than MIN level Low
Parking Brake Sw Parking brake lever pulled
ON
Parking brake lever released OFF
Rear Defogger Sw Rear end door window defogger switch turned ON with engine 
running
ON
Rear end door window defogger switch turned OFF with engine 
running OFF
Tail Light Sw Lighting switch at HEAD 
or CLEARANCE position ON
Lighting switch at OFF position OFF
Driv Seatbelt Sw Driver side seat belt fastened
Fasten
Driver side seat belt unfastened Unfasten
Rear end door opener Rear end door open
ON
Rear end door closed OFF
“3” Position Sw A/T select lever at 2nd or 3rd position with ignition switch turned 
ON
ON
A/T select lever at other than 2nd or 3rd position with ignition 
switch turned ON OFF
Charge Lamp Engine at stop with ignition switch turned ON
ON
Engine running OFF
Oil pressure switch Engine at stop with ignition switch turned ON
ON
Engine running OFF
A/C Switch A/C and ignition switch turned ON
ON
A/C switch turned OFF OFF  
Page 1416 of 1496
Downloaded from www.Manualslib.com manuals search engine 10B-13 Body Electrical Control System: 
Scan Tool Data Definitions
Vehicle Speed (km/h, mph):  It is computed based on pulse signals from vehicle speed sensor on transmission.
Outside air Temp ( °C,  °F):   It is detected by outside air temperature sensor.
Battery Voltage (V):   This parameter indicates battery po sitive voltage inputted to BCM.
Coolant Temp (Engine coolant temperature) ( °C,  °F):   It is detected by engine coolant temperature sensor.
Engine Speed (RPM):   It is computed by reference pulse signals from CMP sensor.
Fuel Consumption (km/l):   This parameter indicates the fuel consumption computed by ECM.
Key Reminder Sw (Key reminder  switch) (Pulled / Key in):  This parameter indicates the state of the key reminder 
switch.
Rear Wiper Sw (Rear wiper switch) (ON / INT / OFF):   This parameter indicates the state of the rear wiper switch.
Door key Sw (Door key cylinder switch) (Lock / Neutral / Unlock):   This parameter indicates the state of the door 
key cylinder switch.
Door lock Sw (Manual door lock switch) (Lock / Neutral / Unlock):   This parameter indicates the state of the 
manual door lock switch.
Driv Door Sw (Driver side d oor switch) (Open / Close):   This parameter indicates the state of the driver side door 
switch.
Pass Door Sw (Other than driver  side door switch) (Open / Close):   This parameter indicates the state of the door 
switches other than driver side door switch.
Brake Fluid Level (Low / Normal):   Low: Brake fluid level is lower than specified level.
Normal: Brake fluid level  is higher than MIN level.
Parking Brake Sw (Parking brake switch) (ON / OFF):   ON: Parking brake lever is pulled up.
OFF: Parking brake lever is released.
Rear Defogger Sw (Rear end door window defogger switch) (ON / OFF):   This parameter indicates the state of 
the rear end door window defogger switch.
Tail Light Sw (Lighting switch) (ON / OFF):   This parameter indicates the state of the lighting switch.
Driv Seatbelt Sw (Driver seat belt switch) (Fasten / Unfasten):   This parameter indicates the state of the driver 
side seat belt buckle switch.
Rear end Door Opener (Rear end door opener switch) (ON / OFF):   This parameter indicates the state of the rear 
end door opener switch.
“3” position Sw (ON/OFF):   This parameter indicates the state of the “3 ” position switch included in A/T manual 
selector assembly.
Charge lamp (ON / OFF):   This parameter indicates the state of the charge system monitor switch.
Oil pressure switch (ON / OFF):   This parameter indicates the state of the oil pressure switch.
A/C Switch (ON / OFF):   This parameter indicates the state of the air conditioning switch.
Diagnosis Using Output Test Function of SUZUKI Scan Tool
SUZUKI scan tool has the output test  function which can force operation of following actuators and relays of the 
system controlled by BCM. When a malf unction is found in the system controlled by BCM, execute the output test 
which enables easy judgment whether the malfunction is on the input side or output side of BCM. For detailed 
information on operation of SUZUKI scan tool,  refer to “SUZUKI Scan Tool Operator’s Manual”.
Output Teat Item Controlled Parts
Hazard Warning Light Turn signal and hazard warning relay
Interior (Dome) Light Interior (Dome) light (wh en interior light switch is at DOOR position)
Door Each door lock actuator
Rear end door open Rear end door opener relay
Warning buzzer Warning buzzer (in BCM)
Rear wiper Rear wiper relay
Alarm indicator Theft deterrent light  (in information display or clock)
Rear defogger Rear end door window defogger relay  
Page 1417 of 1496
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DTC TableS7RS0BA204004
DTC CheckS7RS0BA204005
Using SUZUKI Scan Tool1) Prepare SUZUKI scan tool.
2) With ignition switch turned OFF, connect it to data  link connector (DLC) located on underside of 
instrument panel of driver’s side.
Special tool
(A):  SUZUKI scan tool 3) Turn ignition switch ON.
4) Read DTC according to 
instructions displayed on 
SUZUKI scan tool and print it or write it down.
Refer to SUZUKI scan tool operator’s manual for 
further details.
If communication between  SUZUKI scan tool and 
BCM is not possible, check if SUZUKI scan tool is 
communicable by connecting it to BCM in another 
vehicle. If communication is  possible in this case, 
SUZUKI scan tool is in good condition. Then check 
data link connector and serial data line (circuit) in the 
vehicle with which communica tion was not possible.
5) After completing the check, turn ignition switch off  and disconnect SUZUKI scan tool from data link 
connector.
DTC 
(displayed 
on SUZUKI  scan tool) DTC (indicated 
by theft 
deterrent light)  DTC (displayed on 
odometer in 
combination meter)  Detected item Detecting condition
NO DTC 0000 0000 — No DTC detected
 )  B1133 1133 b1133 Battery voltage too high Battery voltage too high
 )  B1141 1141 b1141 Outside air temperature 
(ambient temperature) sensor 
circuit openSensor output voltage too high
 )  B1142 1142 b1142 Outside air temperature 
(ambient temperature) sensor 
circuit short to groundSensor output voltage too low
 )  B1150 1150 b1150 Air bag communication circuit 
malfunctionAir bag communication circuit 
open or short to ground
 )  B1157 1157 b1157 Air bag deployment signal input Air bag deployment signal 
inputted
 )  B1170 1170 b1170 EEPROM access error Memory error
 )
U0155 0155 U0155 Lost communication with 
instrument panel cluster (IPC) 
control moduleReceiving error of BCM from 
combination mete
r for specified 
time continuously
 )  U1073 1073 U1073 Control module communication 
bus offTransmitting and receiving error 
of BCM for specified time 
continuously
 )  U1100 1100 U1100 Lost communication with ECM Receiving error of BCM from 
ECM for specified time 
continuously
 )  U1101 1101 U1101 Lost communication with TCM Receiving error of BCM from 
TCM for specified time 
continuously
 )  U1144 1144 U1144 Lost communication with 
keyless start control moduleReceiving error of BCM from 
keyless start control module for 
specified time continuously
(A)
I4RS0BA20005-01  
Page 1418 of 1496
Downloaded from www.Manualslib.com manuals search engine 10B-15 Body Electrical Control System: 
Without Using SUZUKI Scan Tool1) Turn ignition switch to OFF position.
2) Perform following Steps a) to d) within 10 seconds af ter ignition switch is turned ON and engine stops.
a) Turn headlight switch to “SMALL” position.
b) Turn headlight switch to “OFF” position.
c) Repeat Steps a) and b) 2 times.
d) Press and release driver side door switch 3 times.
3) Check DTC displayed on odometer of combination meter or  read flashing pattern of theft deterrent light which 
represents DTC as shown in the following example and write it down.
When more than 2 DTCs are stored in memory, flashing for each DTC starts with the smallest DTC number in 
increasing order. Also, DTC is indicated repeatedly until the ignition switch is turned OFF.
4) After completing the check, turn ignition switch to OFF position.
DTC ClearanceS7RS0BA204006
After repair or replace of malfunction part(s), clear all 
DTCs by performing the following procedure.
Using SUZUKI Scan Tool 1) Connect SUZUKI scan tool to data link connector in  the same manner as when making this connection 
for DTC check.
2) Turn ignition switch ON and engine stops.
3) Erase DTC according to instructions displayed on  scan tool. Refer to scan tool operator’s manual for 
further details.
4) After completing the clear ance, turn ignition switch 
off and disconnect scan tool from data link 
connector. Without Using SUZUKI Scan Tool
1) Turn ignition switch to OFF position.
2) Perform following Steps a) to d) within 10 seconds  after ignition switch is turned ON and engine stops.
a) Turn headlight switch to “SMALL” position.
b) Turn headlight switch to “OFF” position.
c) Repeat Steps a) and b) 3 times.
d) Press and release driver side door switch 4  times.
3) After completing above Steps, confirm that no  malfunction DTC is detected.
B A
[B] [A]
[C]
B A B A
3
113
3
113
T2
T1 T1 T1 T1
1
2
T2T2
T2
T1 T1 T1 T1T2T2
0
T2
0
T2
0
T2
0
T2
11 6 0
T1 T1 T1
T2
T3T2T2T2
I4RS0AA20007-01
[A]: No DTC (No. 0000) B: Indicator lamp turned OFF1. Theft deterrent light
[B]: DTC B1133 (No. 1133) T1: 0.3 seconds2. Odometer
[C]: When 2 DTCs are detected T2: 1.0 seconds
A: Indicator lamp tur ned ON T3: 3.0 seconds  
Page 1425 of 1496
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ESP® model
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.
[F] E85
161
15
2
3
4
5
6
7
8
9
10
11
12
13
14
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
3233
34
35
36
37
38
39
40
41
42
43
44
45
46
47
[D] 12345678910
11
141516
36 34 33 32 31 30 29 24 23
37
181920
G49
[A]
E23
C37
34
1819
567
10
11
17
20
47 46
495051
2122
52 16
25 9
24
14
29
5557 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
4042 39 38
44
45 43 41 331
1213
238
34
1819
567
10
11
17
20
47 46
495051
2122
52 16
25 9
24
14
29
5557 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
4042 39 38
44
45 43 41 331
12
13
238
[C]G28
1234567
8
910
11
1213141516
1718
19
20
212223242526272829303132
[E] G54
109 321
[B]
G37E46
1234567 1234567
8910
11
8910
11
121314 121314
1516171819202122
4
6 1
2
3
REDWHT
REDWHT
REDWHT
REDWHT
E23-3E23-18
E85-42E85-46
E85-13E85-44
G37-4G37-2
REDWHT
REDWHTG49-19G49-18
5
7
WHTG54-9REDG54-10
G28-8G28-10
G28-7REDG28-9WHT
RED/BLKWHT/BLK
REDWHTE46-1E46-2
G37-1G37-3
+BB8
I7RS0BA20005-01
[A]: ECM connector (viewed from harness side)
1. ECM
[B]: BCM connector (viewed from harness side)  2. ESP® control module
[C]: Combination meter connector (viewed from harness side) 3. BCM
[D]: Keyless start control module connector (viewed from harness side) 4. Steering angle sensor
[E]: Steering angle sensor  connector (viewed from harness side) 5. Combination meter
[F]: ESP ® control module connector (viewed from terminal side) 6. Keyless start control module
7. CAN junction connector
8. Data link connector (DLC)
DTC detecting condition Trouble area
BCM can not receive CAN data from combination meter 
for longer than specif ied time continuously. • CAN communication circuit
•BCM
• Combination meter  
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.