oil pressure INFINITI QX56 2008 Factory Service Manual

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

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

BCS
DIAGNOSIS SYSTEM (BCM)BCS-27
< FUNCTION DIAGNOSIS > [BCM]
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AIR PRESSURE MONITOR
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

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

CCS
INSPECTION AND ADJUSTMENTCCS-5
< BASIC INSPECTION >
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INSPECTION AND ADJUSTMENT
ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT
ADDITIONAL SERVICE WHEN REPL ACING CONTROL UNIT : Description
INFOID:0000000001731800
Always perform the laser beam aiming adjustment after repl acing the ICC unit. In addition, test the ICC sys-
tem operations to see if it functions normally.
ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT : Special Repair Re-
quirement
INFOID:0000000001731801
1.LASER BEAM AIMING ADJUSTMENT
Adjust laser beam aiming. Refer to CCS-5, "
LASER BEAM AIMING ADJUSTMENT : Outline of Laser Beam
Aiming Adjustment Procedure".
>> GO TO 2
2.ICC SYSTEM ACTION TEST
1. Perform the ICC system operation test. Refer to CCS-8, "
ACTION TEST : ICC System Running Test".
2. Check that the ICC system operates normally.
>> INSPECTION END.
LASER BEAM AIMI NG ADJUSTMENT
LASER BEAM AIMING ADJUSTMENT : Outlin e of Laser Beam Aiming Adjustment
Procedure
INFOID:0000000001756724
CAUTION:
• The laser beam aiming adjustment can not be performed without CONSULT-III.
• The laser beam aiming adjustment must be performed every time the ICC sensor is removed,
installed or has been moved as a result of a collision.
1. Prepare the vehicle and the work area.
2. Set up the ICC target board. For details, refer to Technical Service Bulletin.
3. Adjust the sensor following the procedure on CONSULT-III.
4. Check system operation after the adjustment.
LASER BEAM AIMING ADJU STMENT : PreparationINFOID:0000000001756725
• Place the vehicle on level ground. Shift the transmi ssion into "P" position and release the parking brake.
• Adjust the tire pressure to the specified value.
• See that there is no load in the vehicle. Coolant , engine oil and fuel should be filled to correct level.
• Check that the vehicle suspension has been adjusted to the standard height by the load leveling rear air sus-
pension system. Refer to SCS-7, "
CONSULT-III Function" .
• Clean the sensor with a soft cloth. Tool number : KV99110100 (J-45718)
LKIA0632E
Revision: March 2010
2008 QX56

CO-4
< PREPARATION >
PREPARATION
PREPARATION
PREPARATION
Special Service ToolINFOID:0000000001538853
The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Tool number
(Kent-Moore No.)
Tool name Description
K V 1 0 1111 0 0
(J-37228)
Seal cutter Removing steel oil pan and rear timing chain
case
WS39930000
(—)
Tube pressure Pressing the tube of liquid gasket
EG17650301
(J-33984-A)
Radiator cap tester adapter Adapting radiator cap tester to radiator cap
and radiator filler neck
a: 28 (1.10) dia.
b: 31.4 (1.236) dia.
c: 41.3 (1.626) dia.
Unit: mm (in)
KV991J0010
(J-23688)
Engine coolant refractometer Checking concentration of ethylene glycol in
engine coolant
KV991J0070
(J-45695)
Coolant refill tool For refilling engine cooling system
—
(J-24460-92)
Radiator pressure test adapter set Adapting radiator pressure tester to reservoir
filler neck.
NT046
S-NT052
S-NT564
WBIA0539E
LMA053
AWBIA0891ZZ
Revision: March 2010
2008 QX56

ENGINE COOLANTCO-11
< ON-VEHICLE MAINTENANCE >
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Changing Engine CoolantINFOID:0000000001538859
WARNING:
• To avoid being scalded, never change the coolant when the engine is hot.
• Wrap a thick cloth around the cap to carefully remo
ve the cap. First, turn the cap a quarter of a turn
to release any built-up pressure, then push down and turn the cap all the way to remove it.
DRAINING ENGINE COOLANT
1. Turn ignition switch ON and set temperature control lever all the way to HOT position or the highest tem-
perature position. Wait 10 seconds and turn ignition switch OFF.
2. Remove the engine front undercover using power tool.
3. Open the radiator drain plug at the bottom of the radiator, and remove the radiator filler cap. This is the only step required
when partially draining the cooling system (radiator only).
CAUTION:
Do not to allow the coolant to contact the drive belts.
4. When draining all of the coolant in the system for engine removal or repair, it is necessary to drain the cylinder block.
Remove the RH cylinder block drain plug to drain the right bank
and the oil cooler hose to drain the left bank as shown.
5. Remove the reservoir tank to drain the engine cool ant, then clean the reservoir tank before installing it.
6. Check the drained coolant for contaminants such as rust, corrosion or discoloration. If the coolant is contaminated, flush the engine cooling system. Refer to CO-11, "
Changing Engine Cool-
ant".
REFILLING ENGINE COOLANT
1. Close the radiator drain plug. Install the reservoir tank, cylinder block drain plug, and the oil cooler hose, if
removed for a total system drain or for engine removal or repair.
• The radiator must be complete ly empty of coolant and water.
• Apply sealant to the threads of the cylinder block drain plug. Use Genuine High Performance Thread Sealant or equivalent. Refer to GI-15, "
Recommended Chemical Products and Sealants".
WBIA0391E
PBIC0146E
WBIA0392E
Revision: March 2010 2008 QX56

DLN-10
< FUNCTION DIAGNOSIS >[ATX14B]
4WD SYSTEM
FUNCTION DIAGNOSIS
4WD SYSTEM
System DiagramINFOID:0000000001737096
COMPONENT DESCRIPTION
WDIA0164E
Components
Function
Transfer control unit Controls transfer control device, control valves and shifts between 2WD/4WD and 4H/4LO.
Transfer control device Integrates actuator motor and actuator position switch.
2-4WD shift solenoid valve Controls oil pressure and allows shifting between 2WD and 4WD.
Clutch pressure solenoid valve Controls oil pressure and distributes torque between front and rear tires.
Line pressure switch Detects line pressure.
Clutch pressure switch Detects clutch pressure.
Transfer fluid temperature sensor Detects transfer fluid temperature.
Actuator motor Moves shift rods when signaled by transfer control unit.
Actuator position switch Detects actuator motor position.
Wait detection switch Detects whether or not 4WD lock gear is locked.
4LO switch Detects if transfer case is in 4LO.
ATP switch Detects if transfer case is in neutral.
4WD shift switch Allows driver to select from 2WD/4WD, 4H/4LO and AUTO.
4WD warning lamp • Illuminates if malfunction is detected in 4WD system.
• Flashes (1 flash / 2 seconds) if large difference in diameter of front and rear tires.
• Flashes (2 flashes / 1 second) if high transfer fluid temperature is detected.
AT P w a r n i n g l a m p Indicates that A/T parking mechanism does not operate when A/T selector lever is in P position
because transfer case is in neutral.
4WD shift indicator lamp Displays driving range selected by 4WD shift switch.
4LO indicator lamp Displays 4LO range.
Revision: March 2010 2008 QX56

DLN-14
< FUNCTION DIAGNOSIS >[ATX14B]
4WD SYSTEM
• Displays 4LO condition while engine is running. 4LO indicator lamp flashes if transfer gear does not shift
completely under 2WD, AUTO, 4H ⇔4LO. (When 4WD warning lamp is turned on, 4LO indicator lamp is
turned off.)
• Turns ON for approximately 1 second when ignition switch is turned ON, for purpose of lamp check.
4WD WARNING LAMP
Turns on or flashes when there is a malfunction in 4WD system.
Also turns on when ignition switch is turned ON, for purpose of lamp che\
ck. Turns OFF approximately 1 sec-
ond after the engine starts if system is normal.
4WD Warning Lamp Indication
ATP WARNING LAMP
When the A/T selector lever is in P position, the vehicle may move if the transfer case is in neutral. ATP warn-
ing lamp is turned on to indicate this condition to the driver.
LINE PRESSURE SWITCH
• With the transfer system design, control of the oil pressure provides the transmission of drive torque to the
front wheels. The main pressure to control the oil pressure is referred to as the line pressure.
• The line pressure switch determines whether or not adequate line pressure has built up under different oper- ating conditions.
• The line pressure switch closes when line pressure is produced.
• The line pressure switch senses line pressure abnormalities and turns the 4WD warning lamp ON.
CLUTCH PRESSURE SWITCH
• The clutch pressure switch determines whether or not adequate clutch pressure has built up under different
operating conditions.
• The clutch pressure switch closes when clutch pressure is produced.
• The clutch pressure switch senses clutch pressure abnormalities and turns the 4WD warning lamp ON.
WAIT DETECTION SWITCH
• The wait detection switch operates when there is circulating torque produced in the propeller shaft (L→H) or
when there is a phase difference between 2-4 sleeve and clutch drum (H →L). After the release of the circu-
lating torque, the wait detection switch helps provi de the 4WD lock gear (clutch drum) shifts. A difference
may occur between the operation of the 4WD shift swit ch and actual drive mode. At this point, the wait
detection switch senses an actual drive mode.
• The wait detection switch operates as follows.
- 4WD lock gear (clutch drum) locked: ON
- 4WD lock gear (clutch drum) released: OFF
• The wait detection switch senses an actual drive mode and the 4WD shift indicator lamp indicates the vehi-
cle drive mode.
ATP SWITCH
ATP switch detects if transfer case is in neutral by the position of the L-H shift fork.
NOTE:
Transfer case may be in neutral when shifting between 4H-4LO.
NEUTRAL-4LO SWITCH
The neutral-4LO switch detects that transfer gear is in neutral or 4LO (or shifting from neutral to 4LO) condi-
tion by L-H shift fork position.
Condition 4WD warning lamp
System normal OFF
Lamp check Turns ON when ignition switch is turned ON.
Turns OFF after engine start.
4WD system malfunction ON
During self-diagnosis Flashes malfunction mode.
Large difference in diameter of front/
rear tires Flashes slow (1 flash / 2 seconds)
(Continues to flash until the ignition switch is turned OFF)
High fluid temperature in transfer case Flashes rapidly (2 flashes / 1 second)
(Continues to flash until fluid temperature returns to normal)
Revision: March 2010 2008 QX56

4WD SYSTEMDLN-15
< FUNCTION DIAGNOSIS > [ATX14B]
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TRANSFER FLUID TEMPERATURE SENSOR
The transfer fluid temperature sensor detects the trans fer fluid temperature and sends a signal to the transfer
control unit.
TRANSFER MOTOR
• The transfer motor drives the sub-oil pump to provi de proper lubrication and oil pressure control when the
vehicle is at standstill, during low-speed operations or is being driven in reverse.
• The main oil pump is operated by the driving force of t he mainshaft. In other words, sufficient oil pressure
buildup does not occur when the vehicle is at standsti ll or during low-speed operations. While the vehicle is
being driven in reverse, the main oil pump rotates in the reverse direction. Therefore the main oil pump does
not discharge oil pressure. During any of the above vehi cle operations, the transfer motor drives the sub-oil
pump to compensate for insufficient oil pressure.
• The transfer motor operates as follows:
- The motor relay turns OFF in the 2WD mode.
- The motor relay operates as described in the table below in modes other than the 2WD mode.
• 4WD shift switch, transmission range switch, Neutral-4LO switch, vehicle speed sensor and throttle position
sensor are used in conjunction with the transfer motor.
Transfer Motor Relay Operation
*: After 2.5 seconds have elapsed.
CLUTCH PRESSURE SOLENOID VALVE
The clutch pressure solenoid valve distributes front and rear torque in AUTO mode.
2-4WD SHIFT SOLENOID VALVE
The 2-4WD shift solenoid valve operates to apply oil pressure to the wet-multiplate clutch, depending on the
drive mode. The driving force is transmitted to the front wheels through the clutch so the vehicle is set in the
4WD mode. Setting the vehicle in the 2WD mode requires no pressure buildup. In other words, pressure force
applied to the wet-multiplate clutch becomes zero.
TRANSFER CONTROL DEVICE
Integrates actuator motor and actuator position switch.
4WD shift switch A/T selector lever position Vehicle speed
(VSS) Accelerator pedal position Motor relay drive
command
2WD ———OFF
4H (LOCK) and 4LO N position
0— ON
P position 00 - 0.07/8
OFF*
0.07/8 - 1/8 HOLD
1/8 - MAX ON
Other than R position 0 < VSS ≤
50 km/h (31 MPH)
— ON
50 km/h (31 MPH) < VSS < 55 km/h (34 MPH) HOLD
55 km/h (34 MPH) ≤ VSS OFF
R position —— ON
R position —— ON
AUTO P or N position 0
0 - 0.07/8
OFF*
0.07/8 - 1/8 HOLD
1/8 - MAX ON
0 < VSS ≤ 50 km/h (31 MPH)
— ON
50 km/h (31 MPH) < VSS < 55 km/h (34 MPH) HOLD
55 km/h (34 MPH) ≤ VSS OFF
Other than R, P and N posi-
tion 0 < VSS ≤
50 km/h (31 MPH)
— ON
50 km/h (31 MPH) < VSS < 55 km/h (34 MPH) HOLD
55 km/h (34 MPH) ≤ VSS OFF
Revision: March 2010 2008 QX56