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BCS-2
PRECAUTIONS
Revision: 2005 July 2005 FX
PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
AKS007KR
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SRS and SB section of this Service Man-
ual.
WARNING:
To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be per-
formed by an authorized NISSAN/INFINITI dealer.
Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.
Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or
harness connectors.
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BCM (BODY CONTROL MODULE) BCS-3
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BCM (BODY CONTROL MODULE)PFP:284B2
System DescriptionAKS00587
BCM (Body Control Module) controls the operation of various electrical units installed on the vehicle.
BCM FUNCTION
BCM has combination switch reading function for reading the operation of combination switches (light, wiper,
washer and turn signal) in addition to a function for controlling the operation of various electrical components.
Also it has an interface function allowing it to receive signals from the unified meter and A/C amp., and send
signals to ECM using CAN communication.
COMBINATION SWITCH READING FUNCTION
Description
BCM reads combination switch (lighting switch, wiper switch) status, and controls various electrical com-
ponent according to the result.
BCM reads information of a maximum of 20 switches by combining five output terminals (OUTPUT 1-5)
and five input terminals (INPUT 1-5).
Operation Description
BCM activates transistors of output terminals (OUTPUT 1-5) periodically, and allows current to flow in
turn.
If any (1 or more) switches are turned ON, circuit of output terminals (OUTPUT 1-5) and input terminals
(INPUT 1-5) becomes active.
At this time, transistors of output terminals (OUTPUT 1-5) are activated to allow current to flow. When volt-
age of input terminals (INPUT 1-5) corresponding to that switch changes, interface in BCM detects volt-
age change, and BCM determines that switch is ON.
SKIA4958E
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BCS-4
BCM (BODY CONTROL MODULE)
Revision: 2005 July 2005 FX
Operation Table Of BCM and Combination Switches
BCM reads operation status of combination switch using combinations shown in table below.
NOTE:
Headlamp system has a dual switch.
SKIA4959E
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BCM (BODY CONTROL MODULE) BCS-5
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Sample Operation: (When Lighting Switch 1ST Position Turned ON)
When lighting switch 1ST position is turned ON, contact in combination switch turns ON. At this time if
OUTPUT 4 transistor is activated, BCM detects that voltage changes in INPUT 5.
When OUTPUT 4 transistor is ON, BCM detects that voltage changes in INPUT 5, and judges that lighting
switch 1ST position is ON. Then BCM sends tail lamp and clearance lamp request signal to IPDM E/R
using CAN communication.
When OUTPUT 4 transistor is activated again, BCM detects that voltage changes in INPUT 5, and recog-
nizes that lighting switch 1ST position is continuously ON.
NOTE:
Each OUTPUT terminal transistor is activated at 10 ms intervals. Therefore after switch is turned ON, electri-
cal loads are activated with time delay. But this time delay is so short that it cannot be detected by human
senses.
SKIA4960E
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BCS-6
BCM (BODY CONTROL MODULE)
Revision: 2005 July 2005 FX
Operation Mode
Combination switch reading function has operation modes shown below.
1. Normal status
When BCM is not in sleep status, OUTPUT terminals (1-5) send out ON signal every 10 ms.
2. Sleep status
When BCM is in sleep status, transistors of OUTPUT 1 and 5 stop the output, and BCM enters low
power mode. Mean while OUTPUT 2, 3, and 4 send out ON signal every 60 ms, and accept only input
from lighting switch system.
CAN COMMUNICATION CONTROL
CAN communication allows a high rate of information transmission through the two communication lines (CAN
L line, CAN H line) connecting the various control units in the system. Each control unit transmits/receives
data but selectively reads required data only. For details of signals that are transmitted/received by BCM via
CAN communication, refer to LAN-30, "
CAN Communication Unit" .
PKIB6124E
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BCM (BODY CONTROL MODULE) BCS-7
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BCM STATUS CONTROL
BCM changes its status depending on the operation status in order to save power consumption.
1. CAN communication status
With ignition switch ON, CAN communicates with other control units normally.
Control by BCM is being operated properly.
When ignition switch is OFF, switching to sleep mode is possible.
Even when ignition switch is OFF, if CAN communication with IPDM E/R and combination meter is
active, CAN communication status is active.
2. Sleep transient status
This status shuts down CAN communication when ignition switch is turned OFF.
It transmits sleep request signal to IPDM E/R and combination meter.
Two seconds after CAN communication of all control units stops, sleep transient status is switched to
CAN communication inactive status.
3. CAN communication inactive status
With ignition switch OFF, CAN communication is not active.
With ignition switch OFF, control performed only by BCM is active.
Three seconds after CAN communication of all control units stops, CAN communication inactive status
is switched to sleep status.
4. Sleep status
BCM is activated with low power mode.
CAN communication is not active.
When CAN communication operation is detected, it switches to CAN communication status.
When a state of the following switches changes, it switches to CAN communication state.
–Key switch
–Hazard switch
–Door lock/unlock switch
–Front door switch (driver side, passenger side)
–Rear door switch (LH, RH)
–Back door opener switch
–Combination switch (passing, lighting switch 1ST position, front fog lamp)
–Key fob (lock/unlock signal)
–Key cylinder switch
When control performed only by BCM is required by switch, it shifts to CAN communication inactive
mode.
Status of combination switch reading function is changed.
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BCS-8
BCM (BODY CONTROL MODULE)
Revision: 2005 July 2005 FX
SYSTEMS CONTROLLED BY BCM DIRECTLY
NOTE:
Power supply only. No system control.
SYSTEMS CONTROLLED BY BCM AND IPDM E/R
SYSTEMS CONTROLLED BY BCM AND COMBINATION METER
SYSTEMS CONTROLLED BY BCM AND INTELLIGENT KEY UNIT
System Reference
Power door lock BL-21, "
POWER DOOR LOCK SYSTEM"
Remote keyless entryBL-56, "REMOTE KEYLESS ENTRY SYSTEM"
Power window NOTEGW-15, "POWER WINDOW SYSTEM"
Sunroof NOTERF-10, "SUNROOF"
Room lamp timerLT-159, "INTERIOR ROOM LAMP"
Warning chimeDI-58, "WARNING CHIME"
Rear wiperWW-38, "REAR WIPER AND WASHER SYSTEM"
Low tire pressure warning systemWT-7, "LOW TIRE PRESSURE WARNING SYSTEM"
System Reference
Panic alarm BL-56, "
REMOTE KEYLESS ENTRY SYSTEM"
Theft warningBL-186, "VEHICLE SECURITY (THEFT WARNING) SYSTEM"
IVIS (NATS)BL-213, "IVIS (INFINITI VEHICLE IMMOBILIZER SYSTEM-NATS)"
HeadlampLT- 7 , "HEADLAMP - XENON TYPE -"
LT- 3 9 , "DAYTIME LIGHT SYSTEM"
Auto light systemLT- 5 5 , "AUTO LIGHT SYSTEM"
Parking, license plate and tail lamps
Battery saver control LT-129, "PARKING, LICENSE PLATE AND TAIL LAMPS"
Front fog lamp
LT- 7 9 , "FRONT FOG LAMP"
Front wiperWW-4, "FRONT WIPER AND WASHER SYSTEM"
Rear window defoggerGW-86, "REAR WINDOW DEFOGGER"
System Reference
Warning chime DI-58, "
WARNING CHIME"
Turn signal and hazard warning lampsLT- 9 1 , "TURN SIGNAL AND HAZARD WARNING LAMPS"
Daytime running lightLT- 3 9 , "DAYTIME LIGHT SYSTEM"
System Reference
Intelligent Key BL-89, "
INTELLIGENT KEY SYSTEM"
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BCM (BODY CONTROL MODULE) BCS-9
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MAJOR COMPONENTS AND CONTROL SYSTEM
System Input Output
Remote control entry system key fob
All-door locking actuator
Turn signal lamp (LH, RH)
Intelligent key system Intelligent key unit
All-door locking actuator
Fuel lid Lock actuator
Turn signal lamp (LH, RH)
Combination meter
Power door lock system
Power window main switch
(door lock and unlock switch)
Power window sub switch (passenger side)
(door lock and unlock switch) All-door locking actuator
Power supply (IGN) to power window, sunroof Ignition power supply Power window and sunroof system
Power supply (BAT) to power window, sunroof
and power seat Battery power supply
Power window, sunroof system and
power seat
Panic alarm
Key switch
Key fob IPDM E/R
Theft warning system
All-door switch
Hood switch
Key fob
Power window main switch (door lock and
unlock switch)
IPDM E/R
Security indicator lamp
Auto light system
Optical sensor
Combination switch IPDM E/R
Battery saver control
Ignition switch
Combination switch IPDM E/R
Headlamp Combination switch IPDM E/R
Daytime system
Combination meter
ECM Clearance lamp
Tail lamp Combination switch IPDM E/R
Front fog lamp Combination switch IPDM E/R
Turn signal lamp Combination switch
Turn signal lamp
Combination meter
Hazard lamp Hazard switch
Turn signal lamp
Combination meter
Room lamp timer
Key switch
key fob
Power window main switch (door lock and
unlock switch)
Front door switch driver side
All-door switch Interior room lamp
Key warning chime
Key switch
Front door switch driver side Combination meter
(warning buzzer)
Light warning chime
Combination switch
Front door switch driver side Combination meter
(warning buzzer)
Seat belt warning chime
Combination meter (Seat belt buckle
(driver side) switch)
Ignition switch Combination meter
(warning buzzer)