
Downloaded from www.Manualslib.com manuals search engine 10B-1 Body Electrical Control System:
Control Systems
Body Electrical Control System
Precautions
Precautions in Diagnosing TroubleS6RW0DA200001
• 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 Service in Section 00” before inspection and observe what is
written there.
• Communication of ECM, TCM (A/T model), ABS control module, 4WD control module (if equipped), keyless start
control module (if equipped), combination 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 referring to “Precaution for CAN Communication System in Section 00”.
General Description
BCM General DescriptionS6RW0DA201001
The Body electrical Control Module (BCM) is
incorporated in junction block. Do not attempt removal of
BCM from junction block 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 (if equipped)
• Keyless entry (if equipped)
• Door lock function of keyless 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 (if equipped)
• Theft deterrent light
Also, the BCM has a function to cause the interior light
and open door warning light 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
which is controlled by BCM by using the output test
function of SUZUKI scan tool to operate actuator
simulatively.
CAN Communication System DescriptionS6RW0DA201002
Refer to “CAN Communication System Description in Section 1A” for CAN communication system description.
BCM communication control data with each control module as follows.
BCM Transmission Data
A/C switch ON signal
Electric load signal
Brake fluid level switch signal
Parking brake switch signal
Diagnostic trouble code (DTC)
Illumination ON signal
Seat belt buckle switch signal
Charging system signal
Engine oil pressure switch signal
Door switch status
Door lock statusECMKeyless Start
Control Module
(if equipped) Combination
Meter
BCMTransmit
DATA
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BCM Reception Data
Theft Deterrent LightS6RW0DA201003
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 intervals after the ignition switch is turned off until it is turned
on again. Also, DTCs stored in BCM can be checked by reading the flashing patterns of the theft deterrent light when
diagnosing troubles.
Security Alarm Description (If Equipped)S6RW0DA201005
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 deterrent 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
Engine speed signal
Vehicle speed signal Engine coolant temperature signal
Brake pedal switch signal
A/C refrigerant pressure signal
Fuel consumption signal A/C compressor clutch signal
Engine type signal
Transmission range sensor signal
Combination meter spec 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
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Downloaded from www.Manualslib.com manuals search engine 10B-5 Body Electrical Control System:
1. BCM 23. Brake fluid level switch 45. Passenger side door lock actuator (if equipped)
2. Rear end door opener actuator (if equipped) 24. Parking brake switch 46. Rear door lock actuator (if equipped)
3. Rear end door opener relay (if equipped) 25. Door key cylinder switch (included in door lock
actuator) (if equipped)47. Hazard warning switch
4. Rear washer motor 26. Manual door lock switch (if equipped) 48. Turn signal and hazard warning relay
5. Rear wiper and washer switch 27. Rear end door opener switch (if equipped) 49. To turn signal light
6. Outside air temperature sensor (if equipped) 28. A/C switch (if equipped) 50. Interior light
7. Key reminder switch 29. Rear end door window defogger switch 51. Rear end door window defogger relay
8. Theft deterrent light 30. Rear wiper motor 52. Right side door mirror heater (if equipped)
9. Oil pressure switch 31. Rear wiper relay 53. Left side door mirror heater (if equipped)
10. SDM 32. TCM (A/T model) 54. Rear end door window defogger
11. P/S control module 33. ECM 55. Rear end door window defogger indicator light
12. Navigation (if equipped) 34. ABS control module 56. Horn relay
13. Audio unit (if equipped) 35. Keyless start control module (if equipped) 57. Horn switch
14. Headlight leveling control module (if equipped) 36. CAN junction connector 58. Horn
15. Generator 37. Combination meter 59. Lighting switch
16. Information display (if equipped) 38. 4WD control module (if equipped) 60. Ignition switch
17. HVAC control module (if equipped) 39. DLC 61. Battery
18. Keyless entry receiver (if equipped) 40. To ABS control module and P/S control module 62. Body ground
19. Driver side door switch 41. To SDM 63. Engine ground
20. Other than driver side door switch 42. To HVAC control module (if equipped)

Downloaded from www.Manualslib.com manuals search engine 10B-7 Body Electrical Control System:
Component Location
BCM and Related System Component LocationS6RW0DA203001
13
12 17 18
21 19
14
24 25
2526
2722 23
22
2476
20
11
5
151615
16 [A] [B]
2
9
10
3
8
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[A]: Auto A/C 9. Rear end door opener switch (if equipped) 19. Lighting switch
[B]: Manual A/C 10. Rear end door opener actuator (incorporated in
door switch)20. Manual door lock switch (if equipped)
1. Generator 11. Keyless entry receiver or keyless start control
module (if equipped)21. Key reminder switch (included in ignition switch)
2. Brake fluid level switch 12. Parking brake switch 22. Junction block
3. ECM 13. Seat belt buckle switch 23. BCM
4. Oil pressure switch 14. Theft deterrent light 24. Horn relay
5. Outside air temperature sensor (if equipped) 15. Rear end door window defogger switch 25. Rear wiper relay
6. Door lock actuator (incorporated in key
cylinder switch)16. A/C switch (if equipped) 26. Rear end door window defogger relay
7. Door switch 17. Hazard warning switch 27. Turn signal and hazard warning relay
8. Interior light 18. Rear wiper switch

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Scan Tool Data Definitions
Vehicle Speed (km/h, mph): This parameter indicates the vehicle speed computed by ECM.
Outside air Temp (°C, °F): It is detected by outside air temperature sensor.
Battery Voltage (V): This parameter indicates battery positive 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 door 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 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.
Headlight Sw (Headlight switch) (ON / OFF) (Junction block without BCM type): This parameter indicates the
state of the lighting switch.
Tail Light Sw (Lighting switch) (ON / OFF): This parameter indicates the state of the lighting switch.
Front Fog Light Sw (Front fog light switch) (ON / OFF) (Junction block without BCM type): This parameter
indicates the state of the front fog light 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.
Charge light (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 malfunction 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”.
NOTE
*1: Junction block without BCM type
*2: With security alarm system
Output Teat Item Controlled Parts
Hazard Warning Light Turn signal and hazard warning relay
Interior (Dome) Light Interior (Dome) light (when interior light switch is at DOOR position)
Tail Light*
1Tail light relay
Front Fog Light*1Front fog light relay (when lighting switch is at HEAD position)
Rear defogger Rear end door window defogger relay
Dead lock Each door lock actuator
Rear end door open Rear end door opener relay
Door Each door lock actuator
Warning Buzzer Warning buzzer (in BCM)
Rear wiper Rear wiper relay
Alarm indicator Theft deterrent light (in information display or clock)
Horn*
2Horn relay

Downloaded from www.Manualslib.com manuals search engine 10B-13 Body Electrical Control System:
DTC TableS6RW0DA204004
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 b1141Outside air temperature
(ambient temperature)
sensor circuit openSensor output voltage too high
) B1142 1142 b1142Outside air temperature
(ambient temperature)
sensor circuit short to
groundSensor output voltage too low
) B1150 1150 b1150Air bag communication
circuit malfunctionAir bag communication circuit
open or short to ground
) B1157 1157 b1157Air bag deployment signal
inputAir bag deployment signal
inputted
) B1170 1170 b1170 EEPROM access error Memory error
) U0073 0073 U0073Control module
communication bus offTransmitting and receiving
error of BCM for specified time
continuously
) U0100 0100 U0100Lost communication with
ECMReceiving error of BCM from
ECM for specified time
continuously
) U0101 0101 U0101Lost communication with
TCMReceiving error of BCM from
TCM for specified time
continuously
) U0155 0155 U0155Lost communication with
instrument panel cluster
(IPC) control moduleReceiving error of BCM from
combination meter for
specified time continuously
) U1144 1144 U1144Lost communication with
keyless start control moduleReceiving error of BCM from
keyless start control module
for specified time continuously

Downloaded from www.Manualslib.com manuals search engine Body Electrical Control System: 10B-20
DTC B1157 (No. 1157) Air Bag Deployment Signal InputS6RW0DA204011
Wiring Diagram
Refer to “DTC B1150 (No. 1150): Air Bag Communication Circuit Malfunction”.
DTC Detecting Condition and Possible Cause
Flow Test Description
Step 1: Check DTC for SDM.
DTC Troubleshooting
DTC B1170 (No. 1170): EEPROM Access ErrorS6RW0DA204012
DTC Detecting Condition and Possible Cause
DTC Troubleshooting
NOTE
Before performing steps below, be sure to perform “Body Electrical Control System Check”.
1) Ignition switch OFF.
2) Replace BCM.
3) Repeat BCM Check Flow Table.
DTC U0073 (No. 0073): Control Module Communication Bus OffS6RW0DA204013
Refer to “Troubleshooting for CAN-DTC in Section 1A”.
DTC U0100 (No. 0100): Lost Communication with ECMS6RW0DA204014
Refer to “Troubleshooting for CAN-DTC in Section 1A”.
DTC U0101 (No. 0101): Lost Communication with TCMS6RW0DA204018
Refer to “Troubleshooting for CAN-DTC in Section 1A”.
DTC U0155 (No. 0155): Lost Communication with Instrument Panel Cluster (IPC) Control ModuleS6RW0DA204015
Refer to “Troubleshooting for CAN-DTC in Section 1A”.
DTC U1144 (No. 1144): Lost Communication with Keyless Start Control ModuleS6RW0DA204016
Refer to “Troubleshooting for CAN-DTC in Section 1A”. DTC detecting condition Possible cause
Air bag deployment signal is fed from SDM to BCM. • Air bag component parts
• BCM malfunction
Step Action Yes No
1DTC check of SDM
1) Check DTC stored in SDM referring to “DTC Check in
Section 8B”.
Is DTC B1021 detected?Go to “DTC B1021:
Front Air Bag
Deployment Record in
Section 8B”.Substitute a known-
good BCM (included in
junction block) and
recheck.
DTC detecting condition Possible cause
Data write error or check sum error. BCM malfunction

Downloaded from www.Manualslib.com manuals search engine Immobilizer Control System: 10C-1
Control Systems
Immobilizer Control System
Precautions
Precautions in Diagnosing TroublesS6RW0DA300001
• Before confirming the diagnostic trouble code (DTC),
do not disconnect connector from ECM, battery cable
from battery, ground wire harness, or main fuse. Such
disconnection will erase DTC stored in ECM.
• DTC stored in ECM memory can be checked as well
as cleared by using SUZUKI scan tool. Before using
SUZUKI scan tool, read its operator’s manual
carefully to know how to use it and what functions are
available.
• Be sure to read “Precautions for Electrical Circuit
Service in Section 00” before inspection.
• Communication of ECM, BCM, ABS control module,
TCM (if equipped), 4WD control module (if equipped),
keyless start control module (if equipped),
combination meter and DLC is established by CAN
(Controller Area Network). Therefore, handle CAN
communication lines with care referring to “Precaution
for CAN Communication System in Section 00”.
For CAN communication system, refer to description
on “CAN Communication System Description in
Section 1A”.
Precaution in Replacing ECMS6RW0DA300002
• If ECM is replaced with new or used one without
Immobilizer control function, the engine will not be
started. In case of the above, check if the newly
installed ECM has Immobilizer control function.
• 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. Or, the
engine cannot be started up. For the registration
procedure, refer to “Procedure after ECM
Replacement”.
Precaution in Replacing Ignition KeyS6RW0DA300003
To register ignition key in case of replacing key(s) and/or
making spare key(s), the transponder code in the ignition
key is registered with ECM. Or the engine can not be
started up. For the registration procedure, refer to
“Registration of the Ignition Key”.
Precautions in Handling Immobilizer Control
System
S6RW0DA300004
• Do not turn ON ignition switch with ignition key in
contact with another one or quite close to another
one. Or, the immobilizer control system may detect
some abnormal condition and prevent the engine from
starting.
• Do not turn ON ignition switch by using ignition key
with any type of metal (1) wrapped its grip or in
contact with it. Or, the immobilizer control system may
detect some abnormal condition and prevent the
engine from starting.
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