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BCS-12
< FUNCTION DIAGNOSIS >[BCM]
SIGNAL BUFFER SYSTEM
SIGNAL BUFFER SYSTEM
System DiagramINFOID:0000000001696407
System DescriptionINFOID:0000000001696408
OUTLINE
BCM has the signal transmission function that output
s/transmits each input/received signal to each unit.
Signal transmission function list
ALMIA0263GB
Signal nameInputOutputDescription
Oil pressure switch signal IPDM E/R (CAN) Combination meter (CAN)Transmits the received oil pres-
sure switch signal via CAN
communication.
Revision: March 2010
2008 QX56
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![INFINITI QX56 2008 Factory Service Manual BCS-26
< FUNCTION DIAGNOSIS >[BCM]
DIAGNOSIS SYSTEM (BCM)
ACTIVE TEST
*: Each lamp switch is in ON position.
TRUNK
TRUNK : CONSULT-III Function (BCM - TRUNK)INFOID:0000000001696427
DATA MONITOR
ACTIVE INFINITI QX56 2008 Factory Service Manual BCS-26
< FUNCTION DIAGNOSIS >[BCM]
DIAGNOSIS SYSTEM (BCM)
ACTIVE TEST
*: Each lamp switch is in ON position.
TRUNK
TRUNK : CONSULT-III Function (BCM - TRUNK)INFOID:0000000001696427
DATA MONITOR
ACTIVE](/manual-img/42/57030/w960_57030-390.png)
BCS-26
< FUNCTION DIAGNOSIS >[BCM]
DIAGNOSIS SYSTEM (BCM)
ACTIVE TEST
*: Each lamp switch is in ON position.
TRUNK
TRUNK : CONSULT-III Function (BCM - TRUNK)INFOID:0000000001696427
DATA MONITOR
ACTIVE TEST
RETAINED PWR
RETAINED PWR : CONSULT-III Function (BCM - RETAINED PWR)INFOID:0000000001696428
Data monitor
SIGNAL BUFFER
SIGNAL BUFFER : CONSULT-III Fu
nction (BCM - SIGNAL BUFFER)INFOID:0000000001696429
DATA MONITOR
ACTIVE TEST
I-KEY LOCK [ON/OFF] Lock signal status received from Intelligent Key unit by CAN communication
I-KEY UNLOCK [ON/OFF] Unlock signal status received from Intelligen t 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 Intelligent 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.
Revision: March 2010 2008 QX56
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![INFINITI QX56 2008 Factory Service Manual BCS
DIAGNOSIS SYSTEM (BCM)BCS-27
< FUNCTION DIAGNOSIS > [BCM]
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AIR PRESSURE MONITOR : Diagnosis DescriptionINFOID:0000000001696430
DESCRIPTION
During INFINITI QX56 2008 Factory Service Manual BCS
DIAGNOSIS SYSTEM (BCM)BCS-27
< FUNCTION DIAGNOSIS > [BCM]
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AIR PRESSURE MONITOR : Diagnosis DescriptionINFOID:0000000001696430
DESCRIPTION
During](/manual-img/42/57030/w960_57030-391.png)
BCS
DIAGNOSIS SYSTEM (BCM)BCS-27
< FUNCTION DIAGNOSIS > [BCM]
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AIR PRESSURE MONITOR : Diagnosis DescriptionINFOID:0000000001696430
DESCRIPTION
During driving, the TPMS receives the signal transmitt
ed from the transmitter installed in each wheel, when
the tire pressure becomes low. T he control unit (BCM) 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 malfunction experienced since the last erasing operation. Refer to BCS-50, "
DTCIndex".
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-32
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.
Revision: March 20102008 QX56
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![INFINITI QX56 2008 Factory Service Manual 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 swit INFINITI QX56 2008 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 swit](/manual-img/42/57030/w960_57030-403.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
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
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 Equivalent to speedo meter reading
Monitor Item
Condition Value/Status
Revision: March 2010 2008 QX56
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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:0000000001604475
• 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-35, "
Brake Burnishing
Procedure".
WARNING:
• Clean brake pads and shoes wi th a waste cloth, then wipe
with a dust collector.
SBR686C
Revision: March 2010 2008 QX56
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BR-28
< ON-VEHICLE REPAIR >
VACUUM LINES
VACUUM LINES
Removal and InstallationINFOID:0000000004894512
REMOVAL
1. Remove engine room cover. Refer to EM-24, "Removal and Installation"
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
Revision: March 2010 2008 QX56
Page 452 of 4083
BR-32
< ON-VEHICLE REPAIR >
FRONT DISC BRAKE
5. Remove torque member bolts, and remove brake caliperassembly.
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 to vehicle, 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
Revision: March 2010 2008 QX56
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BRAKE MASTER CYLINDERBR-37
< DISASSEMBLY AND ASSEMBLY >
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DISASSEMBLY AND ASSEMBLY
BRAKE MASTER CYLINDER
Disassembly and AssemblyINFOID:0000000004894496
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 sensor 3. Grommet
4. Master cylinder assembly 5. Rear pressure sensor6. Front pressure sensor
7. Seal 8. Reservoir tankB. Brake fluid
R. Rubber grease
AWFIA0415GB
Revision: March 2010 2008 QX56