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BCS-12
< FUNCTION DIAGNOSIS >[BCM]
SIGNAL BUFFER SYSTEM
SIGNAL BUFFER SYSTEM
System DiagramINFOID:0000000003776382
System DescriptionINFOID:0000000003776383
OUTLINE
BCM has the signal transmission function that output
s/transmits each input/received signal to each unit.
Signal transmission function list
ALMIA0263GB
Signal name Input Output Description
Oil pressure switch signal IPDM E/R (CAN) Combination meter (CAN) Transmits the received oil pres-
sure switch signal via CAN
communication.
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![INFINITI QX56 2009 Factory Service Manual
BCS-26
< FUNCTION DIAGNOSIS >[BCM]
DIAGNOSIS SYSTEM (BCM)
ACTIVE TEST
*: Each lamp switch is in ON position.
TRUNK
TRUNK : CONSULT-III Fu
nction (BCM - TRUNK)INFOID:0000000003776401
DATA MONITOR
ACTI INFINITI QX56 2009 Factory Service Manual
BCS-26
< FUNCTION DIAGNOSIS >[BCM]
DIAGNOSIS SYSTEM (BCM)
ACTIVE TEST
*: Each lamp switch is in ON position.
TRUNK
TRUNK : CONSULT-III Fu
nction (BCM - TRUNK)INFOID:0000000003776401
DATA MONITOR
ACTI](/manual-img/42/57031/w960_57031-399.png)
BCS-26
< FUNCTION DIAGNOSIS >[BCM]
DIAGNOSIS SYSTEM (BCM)
ACTIVE TEST
*: Each lamp switch is in ON position.
TRUNK
TRUNK : CONSULT-III Fu
nction (BCM - TRUNK)INFOID:0000000003776401
DATA MONITOR
ACTIVE TEST
RETAINED PWR
RETAINED PWR : CONSULT-III Function (BCM - RETAINED PWR)INFOID:0000000003776402
Data monitor
SIGNAL BUFFER
SIGNAL BUFFER : CONSULT-III Fu nction (BCM - SIGNAL BUFFER)INFOID:0000000003776403
DATA MONITOR
ACTIVE TEST
KEY CYL UN-SW [ON/OFF] Unlock switch status input from door key cylinder switch
CDL LOCK SW [ON/OFF] Lock switch status input from door lock and unlock switch
CDL UNLOCK SW [ON/OFF] Unlock switch status input from door lock and unlock switch
I-KEY LOCK [ON/OFF] Lock signal st atus received from Intelligent Key unit by CAN communication
I-KEY UNLOCK [ON/OFF] Unlock signal status received from Intelligent Key unit by CAN communication
Monitor Item
[Unit] Description
Test Item Operation Description
BATTERY SAVER OFF Cuts the interior room lamp power supply to turn interior room lamps OFF.
ON Outputs the interior room lamp power supply to turn interior room lamps ON.*
Monitor Item [Unit] Contents
IGN ON SW [ON/OFF] Indicates condition of ignition switch in ON position
I-KEY TRUNK [ON/OFF] Indicates condition of In telligent Key back door opening operation
TRUNK OPNR SW [ON/OFF] Indicates condition of back door opener switch.
VEHICLE SPEED [ON/OFF] Indicates condition of ve hicle speed signal from combination meter
Test Item Description
TRUNK/BACK DOOR This test is able to check back door open operation.
Back door open when “OPEN” on CONSULT-III screen is touched.
Monitor Item
[Unit] Description
DOOR SW-DR [ON/OFF] Indicates condition of front door switch LH.
DOOR SW-AS [ON/OFF] Indicates condition of front door switch RH.
Monitor Item [Unit] Description
OIL PRESS SW [ON/OFF] Displays the status of oil pressure switch received from IPDM E/R via CAN communication.
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BCS
DIAGNOSIS SYSTEM (BCM)BCS-27
< FUNCTION DIAGNOSIS > [BCM]
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AIR PRESSURE MONITOR
AIR PRESSURE MONITOR : Diagnosis DescriptionINFOID:0000000003776404
DESCRIPTION
During INFINITI QX56 2009 Factory Service Manual
BCS
DIAGNOSIS SYSTEM (BCM)BCS-27
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AIR PRESSURE MONITOR : Diagnosis DescriptionINFOID:0000000003776404
DESCRIPTION
During](/manual-img/42/57031/w960_57031-400.png)
BCS
DIAGNOSIS SYSTEM (BCM)BCS-27
< FUNCTION DIAGNOSIS > [BCM]
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AIR PRESSURE MONITOR : Diagnosis DescriptionINFOID:0000000003776404
DESCRIPTION
During driving, the TPMS receives the signal transmitt
ed from the transmitter installed in each wheel, when
the tire pressure becomes low. The control unit (BC M) of this system has pressure judgment and trouble diag-
nosis functions.
When the TPMS detects low inflation pressure or anot her unusual symptom, the warning lamps in the combi-
nation meter comes on.
SELF DIAGNOSTIC PROCE DURE (WITH CONSULT-III)
With CONSULT-III
Touch “SELF-DIAG RESULTS” display to show malf unction experienced since the last erasing operation.
Refer to BCS-51, "DTC Index"
.
SELF DIAGNOSTIC PROCE DURE (WITHOUT CONSULT-III)
Without CONSULT-III
To start the self-diagnostic results mode, ground terminal of the tire pressure warning check connector. The
malfunction location is indicated by the warning lamp flashing.
NOTE:
When the low tire warning lamp flashes 5 Hz and continues repeating it, the system is normal.
Test Item Operation Description
OIL PRESSURE SW OFF OFF
ON
BCM transmits the oil pressure switch signal to the combination meter via CAN communica-
tion, which operates the oil pressure gauge in the combination meter.
SEIA0745E
Flickering
pattern Items Diagnostic items detected when··· Check item
15 Tire pressure value (Front LH) Front LH tire pressure drops to 181 kPa (1.8 kg/cm, 25.25 psi) or less.
–
16 Tire pressure value (Front RH) Front RH tire pressure drops to 181 kPa (1.8 kg/cm, 25.25 psi) or less.
17 Tire pressure value (Rear RH) Rear RH tire pressure drops to 181 kPa (1.8 kg/cm, 25.25 psi) or less.
18 Tire pressure value (Rear LH) Rear LH tire pressure drops to 181 kPa (1.8 kg/cm, 25.25 psi) or less.
21 Transmitter no data (Front LH) Data from front LH transmitter can not be received.
WT-27
22 Transmitter no data (Front RH) Data from front RH transmitter can not be received.
23 Transmitter no data (Rear RH) Data from Rear RH transmitter can not be received.
24 Transmitter no data (Rear LH) Data from Rear LH transmitter can not be received.
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BCS
BCM (BODY CONTROL MODULE)BCS-39
< ECU DIAGNOSIS > [BCM]
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HEADLAMP SW1
Headlamp switch OFF OFF
Headlamp switch 1st ON
HEADLAMP SW2 Headlamp switch OFF OFF
Headlamp swi INFINITI QX56 2009 Factory Service Manual
BCS
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HEADLAMP SW1
Headlamp switch OFF OFF
Headlamp switch 1st ON
HEADLAMP SW2 Headlamp switch OFF OFF
Headlamp swi](/manual-img/42/57031/w960_57031-412.png)
BCS
BCM (BODY CONTROL MODULE)BCS-39
< ECU DIAGNOSIS > [BCM]
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HEADLAMP SW1
Headlamp switch OFF OFF
Headlamp switch 1st ON
HEADLAMP SW2 Headlamp switch OFF OFF
Headlamp switch 1st ON
HI BEAM SW High beam switch OFF OFF
High beam switch HI ON
H/L WASH SW NOTE:
The item is indicated, but not monitored OFF
IGN ON SW Ignition switch OFF or ACC OFF
Ignition switch ON ON
IGN SW CAN Ignition switch OFF or ACC OFF
Ignition switch ON ON
INT VOLUME Wiper intermittent dial is in a dial position 1 - 7 1 - 7
I-KEY LOCK LOCK button of Intelligent Key is not pressed OFF
LOCK button of Intelligent Key is pressed ON
I-KEY UNLOCK UNLOCK button of Intelligent Key is not pressed OFF
UNLOCK button of Intelligent Key is pressed ON
KEY ON SW Mechanical key is removed from key cylinder OFF
Mechanical key is inserted to key cylinder ON
OIL PRESS SW Ignition switch OFF or ACC
Engine running
OFF
Ignition switch ON ON
PASSING SW Other than lighting switch PASS OFF
Lighting switch PASS ON
REAR DEF SW Rear window defogger switch OFF OFF
Rear window defogger switch ON ON
RKE LOCK AND UN-
LOCK NOTE:
The item is indicated, but not monitored OFF
ON
RR WASHER SW Rear washer switch OFF OFF
Rear washer switch ON ON
RR WIPER INT Rear wiper switch OFF OFF
Rear wiper switch INT ON
RR WIPER ON Rear wiper switch OFF OFF
Rear wiper switch ON ON
RR WIPER STOP Rear wiper stop position OFF
Other than rear wiper stop position ON
TAIL LAMP SW Lighting switch OFF OFF
Lighting switch 1ST ON
TRNK OPNR SW When back door opener switch is not pressed OFF
When back door opener switch is pressed ON
TURN SIGNAL L Turn signal switch OFF OFF
Turn signal switch LH ON
TURN SIGNAL R Turn signal switch OFF OFF
Turn signal switch RH ON
VEHICLE SPEED While driving Equiv alent to speedometer reading
Monitor Item Condition Value/Status
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BR-4
< PRECAUTION >
PRECAUTIONS
5. When the repair work is completed, return the ignition switch to the ″LOCK ″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of a ll control units using CONSULT-III.
Precaution for Brake SystemINFOID:0000000003772409
• Always use recommended brake fluid. Refer to MA-12, "Fluids and Lubricants".
• Do not reuse drained brake fluid.
• Be careful not to splash brake fluid on painted areas.
• To clean or wash all parts of master cylinder, disc brake caliper and wheel cylinder, use clean brake fluid.
• Do not use mineral oils such as gasoline or kerosene. They will ruin rubber parts of the hydraulic system.
• Use flare nut wrench when removing and installing brake tube.
• Always check tightening torque when installing brake lines.
• Before working, turn ignition switch to OFF and disconnect con- nectors for ABS actuator and electric unit (control unit) or battery
terminals.
• Burnish the brake contact surfaces after refinishing or replacing drums or rotors, after replacing pads or linings, or if a soft pedal
occurs at very low mileage. Refer to BR-30, "
Brake Burnishing
Procedure".
WARNING:
• Clean brake pads and shoes wi th a waste cloth, then wipe
with a dust collector.
SBR686C
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BR-28
< ON-VEHICLE REPAIR >
VACUUM LINES
VACUUM LINES
Removal and InstallationINFOID:0000000003772441
REMOVAL
1. Remove engine room cover.
2. Disconnect vacuum hose from hose clip.
3. Release clamps and disconnect vacuum hose.
4. Remove check valve from brake booster.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
• Insert vacuum hose for at least 24 mm (0.94 in).
• Do not use lubricating oil during assembly.
1. Hose clip2. Clamp3. Vacuum hose
4. Check valve
LFIA0216E
SBR225B
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BR-32
< ON-VEHICLE REPAIR >
FRONT DISC BRAKE
NOTE:
Discard the copper washers, do not reuse.
5. Remove torque member bolts, and remove brake caliper assembly.
CAUTION:
Do not drop brake pad.
6. Apply matching marks to disc rotor and wheel hub assembly as shown if the disc rotor is to be reused, then remove disc rotor.
CAUTION:
Put matching marks on wheel hub assembly and disc rotor
if the disc rotor is to be reused.
INSTALLATION
1. If reusing the disc rotor, use the matching marks to align discrotor on the wheel hub assembly as shown, then install disc
rotor using a wheel nut to hold it in place.
CAUTION:
Use matching marks on wheel hub assembly and disc rotor
if the disc rotor is to be reused.
2. Install brake caliper assembly, and tighten torque member bolts to the specified torque.
CAUTION:
Do not allow oil or any moisture on all contact surfaces
between steering knuckle and caliper assembly, bolts, and
washer.
SFIA2437E
SDIA2608E
SDIA2608E
SFIA2437E
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BRAKE MASTER CYLINDERBR-37
< DISASSEMBLY AND ASSEMBLY >
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DISASSEMBLY AND ASSEMBLY
BRAKE MASTER CYLINDER
Disassembly and AssemblyINFOID:0000000004045487
DISASSEMBLY
CAUTION:
• Master cylinder assembly cannot be disassembled.
• Do not drop parts. If a part is dropped, do not use it.
1. Pull the reservoir tank off the master cylinder assembly.
2. Remove the grommets from master cylinder assembly and discard the grommets. CAUTION:
Discard the grommets, do not reuse.
3. Remove the fluid level sensor from the reservoir tank.
4. Remove the front and rear pressure sensors and discard. CAUTION:
Discard the front and rear pressure sensors, do not reuse.
ASSEMBLY
CAUTION:
• Never use mineral oil such as kerosene, g asoline during the cleaning and assembly process.
• Do not drop parts. If a part is dropped, do not use it.
1. Reservoir cap 2. Fluid level sensor3. Grommet
4. Master cylinder assembly 5. Rear pressure sensor 6. Front pressure sensor
7. Seal 8. Reservoir tankB. Brake fluid
R. Rubber grease
AWFIA0415GB
Revision: December 20092009 QX56