2011 INFINITI QX56 alternator

ENGINE ASSEMBLYEM-101
< UNIT REMOVAL AND INSTALLATION >
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5. Remove A/T assembly. Refer to
TM-205, "2WD : Exploded View" (2WD models) or TM-208, "4WD :
Exploded View" (4WD models).
6. Remove steering gear assembly. Refer to ST-41, "
Exploded View".
7. Remove front final drive assembly. Refer to DLN-162, "
Exploded View".
8. Remove exhaust manifold. Refer to EM-40, "
Exploded View".
9. Remove alternator. Refer to CHG-25, "
Exploded View".
Engine Room LH
1. Remove air cleaner and air duct. Refer to EM-27, "Exploded View".
2. Remove A/C compressor. Refer to HA-30, "
Exploded View".
3. Disconnect fuel feed hose and EVAP hose. Refer to EM-43, "
Exploded View".
CAUTION:
Fit plugs onto disconnected hoses to prevent fuel leakage.
Engine Room RH
1. Remove power steering oil pump and reservoir tank. Refer to ST-48, "Exploded View".
2. Disconnect heater hose at heater core side, and fit a plug onto hose end to prevent engine coolant leak-
age.
3. Disconnect ground cable.
4. Disconnect all clips and connectors of the engine harness from vehicle side.
Removal Work
1. Install alternator bracket. Refer to CHG-25, "Exploded View".
 Temporarily tighten mounting bolts.
2. Remove intake manifold. Refer to EM-30, "
Exploded View".
3. Remove starter motor. Refer to STR-17, "
Exploded View".
4. Install engine slingers.
5. Lift using a hoist and secure the engine in position.
6. Remove engine mounting bracket (LH, RH) and engine mounting insulator (LH, RH). Refer to EM-98,
"Exploded View".
7. Remove the engine from the vehi cle, avoid interference with the
vehicle body.
CAUTION:
 Before and during lifting, always check that any har-
nesses are left connected.
 Never damage engine mounti ng insulator and avoid oil/
grease smearing or spills onto engine mounting insulator.
A Engine front slinger (bank 2) B Engine rear slinger C Engine front slinger (bank 1)
Slinger bolts:
: 45.0 N·m (4.6 kg-m, 33 ft-lb)
JPBIA3970ZZ
JPBIA3497ZZ
Revision: 2010 May2011 QX56

OIL PUMPLU-13
< REMOVAL AND INSTALLATION >
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OIL PUMP
Exploded ViewINFOID:0000000006289624
Removal and InstallationINFOID:0000000006289625
REMOVAL
NOTE:
Do not remove the engine assembly to perform this procedure.
1. Disconnect battery cable from
negative terminal. Refer to PG-165, "
Exploded View".
2. Drain engine oil. Refer to LU-8, "
Draining".
3. Drain engine coolant from radiator. Refer to CO-8, "
Draining".
CAUTION:
 Perform this step when engine is cold.
 Never spill engine coolant on drive belts.
4. Remove the following components and related parts:  Air cleaner case assembly and air duct. Refer to EM-27, "
Exploded View".
 Drive belt auto tensioner and idler pulley. Refer to EM-26, "
Exploded View".
 Fan shroud. Refer to CO-13, "
Exploded View".
 Cooling fan, fan coupling and fan bracket. Refer to CO-16, "
Exploded View".
 Front under cover. Refer to EXT-25, "
Exploded View".
 Protector A and B. Refer to SCS-32, "
FRONT TUBE ASSEMBLY : Exploded View".
 Front suspension rear cross member. Refer to TM-205, "
2WD : Exploded View" (2WD models) or TM-
208, "4WD : Exploded View" (4WD models).
 Steering gear assembly. Refer to ST-41, "
Exploded View".
 Front final drive assembly. Refer to DLN-162, "
Exploded View".
 Power steering oil pump. Refer to ST-48, "
Exploded View".
 Alternator, alternator bracket and alternator stay. Refer to CHG-25, "
Exploded View".
 Oil pan (lower) and oil strainer. Refer to EM-54, "
Exploded View".
 Oil pan (upper). Refer to EM-57, "
Exploded View".
 Electric throttle control actuator. Refer to EM-30, "
Exploded View".
 Radiator hoses. Refer to CO-13, "
Exploded View".
 Water suction hose and water suction pipe. Refer to CO-20, "
Exploded View".
 Water pump pulley. Refer to CO-18, "
Exploded View".
 Rocker cover. Refer to EM-33, "
Exploded View".
WBIA0415E
1. Oil pump body 2. Outer rotor 3. Inner rotor
4. Oil pump cover 5. Oil pump drive spacer 6. Regulator valve
7. Regulator spring 8. Regulator plug
Revision: 2010 May2011 QX56

MA-12
< PERIODIC MAINTENANCE >
ENGINE MAINTENANCE
ENGINE MAINTENANCE
DRIVE BELTS
DRIVE BELTS : Exploded ViewINFOID:0000000006394835
DRIVE BELTS : CheckingINFOID:0000000006394836
WARNING:
Be sure to perform the these steps when engine is stopped.
 Check that the indicator (C) (notch on fixed side) of each auto-tensioner is within the possible use range (A).
NOTE:
 Check the each auto-tensioners indication when the engine is cold.
 When new drive belts is installed, the indicator (notch on fixed side) should be within the range (B) in the\
figure.
 Visually check all drive belts for wear, damage or cracks.
 If the indicator (notch on fixed side) is out of the possible use range or drive belts are damaged, replace drive
belts.
DRIVE BELTS : Tension AdjustmentINFOID:0000000006394837
Refer to EM-132, "Drive Belts".
ENGINE COOLANT
ENGINE COOLANT : InspectionINFOID:0000000006394844
LEVEL
1. Drive belt 2. Power steering oil pump pulley 3. Alternator pulley
4. Crankshaft pulley 5. A/C compressor 6. Idler pulley
7. Cooling fan pulley 8. Water pump pulley 9. Drive belt auto-tensioner
A. Possible use range B. Range when new drive belt is in-
stalledC. Indicator
D. View D
JPBIA3264ZZ
Revision: 2010 May2011 QX56

MWI-40
< ECU DIAGNOSIS INFORMATION >
COMBINATION METER
11
(G) Ground Enter switch signal Input Ignition
switch
ONWhen switch (enter
switch) is pressed
0 V
Other than the above 5 V
12
(O) Ground Select switch signal Input Ignition
switch
ONWhen switch (select
switch) is pressed
0 V
Other than the above 5 V
13
(W/R) Ground
Illumination control switch
signal (+) InputIgnition
switch
ON When switch [illumi-
nation control sw
itch (+)] is
pressed 0 V
Other than the above 5 V
14
(R) Ground Illumination control switch
signal (
−) InputIgnition
switch
ON When switch [illumi-
nation control switch (
−)] is
pressed 0 V
Other than the above 5 V
15
(R/W) Ground Air bag signal Input Ignition
switch
ONAir bag warning lamp
ON
4 V
Air bag warning lamp
OFF 0 V
18
(W/R) Ground Ambient sensor signal Input — —
19
(V/W) Ground A/C auto amp. connection
recognition signal Input —When A/C auto amp. is
connected
5 V
Other than the above 0 V
20
(B) Ground Ambient sensor ground — Ignition
switch
ON—0 V
21
(L) —CAN-H — — — —
22
(P) —CAN-L — — — —
23
(B) Ground Ground — Ignition
switch
ON
—0 V
24
(V) Ground Fuel level sensor ground — Ignition
switch
ON—0 V
25
(O/L) Ground Alternator signal Input Ignition
switch
ONCharge warning lamp ON 2 V
Charge warning lamp OFF Battery voltage
26
(W) Ground Parking brake switch signal Input Ignition
switch
ONParking brake applied 0 V
Parking brake released 12 V
Te r m i n a l N o .
(Wire color) Description
ConditionVa l u e
(Approx.)
+ – Signal name Input/
Output
JSNIA0014GB
Revision: 2010 May2011 QX56

PCS-6
< SYSTEM DESCRIPTION >[IPDM E/R]
SYSTEM
NOTE:
BCM controls the starter relay.
RELAY CONTROL SYSTEM : Fail-SafeINFOID:0000000006220163
CAN COMMUNICATION CONTROL
When CAN communication with ECM and BCM is impossible,
IPDM E/R performs fail-safe control. After CAN
communication recovers normally, it also returns to normal control.
If No CAN Communication Is Available With ECM
If No CAN Communication Is Available With BCM
Control relay Input/output Transmi t unit Control part Reference page
 Headlamp low relay
 Headlamp high relay  Low beam request signal
 High beam request signal
BCM (CAN)
 Headlamp (LO)
 Headlamp (HI) EXL-10
Front fog lamp relay Front fog light request signal BCM (CAN) Front fog lamp
EXL-20
Tail lamp relay Position light request signal BCM (CAN) Parking lamp
 License plate
lamp
Tail lamp
 Side marker lamp EXL-18
Illuminations
INL-6
 Front wiper relay
 Front wiper high relayFront wiper request signal BCM (CAN)
Front wiper motorWW-7Front wiper stop position sig-
nal Front wiper motor
Rear window defogger
relay Rear window defogger control
signal
BCM (CAN)
Rear window defog-
ger
DEF-6
Horn relay
 Theft warning horn
relay  Theft warning horn request
signal
 Horn reminder signal BCM (CAN)
Horn (high)
Horn (low) SEC-17
 Starter relayNOTE
 Starter control relayStarter control rela
y signal BCM (CAN)
Starter motorSEC-10
,
SEC-10Steering lock unit condition
signal Steering lock unit
Starter relay control signal TCM
Steering lock relay Steering lock relay signal BCM (CAN)
Steering lock unitSEC-10
Steering lock unit condition
signal Steering lock unit
A/T shift selector (detention
switch) signal A/T shift selector
(detention switch)
A/C relay A/C compressor request sig-
nal ECM (CAN)
A/C compressor
(Magnet clutch) HAC-17
Headlamp washer relay
Headlamp washer request
signal BCM (CAN)Headlamp washer
pump WW-13
 Ignition relay
 Ignition relay-2
 Ignition relay-3Ignition switch ON signal BCM (CAN)
Each control unit,
sensor, actuator and
relay (ignition power
supply)PCS-29Vehicle speed signal
Combination meter
(CAN)
Push-button ignition switch
signal Push-button ignition
switch
Control part Fail-safe operation
Cooling fan  Transmits the pulse duty signal (PWM signal) 100% when the ignition switch is turned ON.
 Transmits the pulse duty signal (PWM signal) 0% when the ignition switch is turned OFF.
A/C compressor A/C relay OFF
Alternator Transmits the power generation command signal (PWM signal) 0%
Revision: 2010 May2011 QX56

PCS-8
< SYSTEM DESCRIPTION >[IPDM E/R]
SYSTEM
POWER CONTROL SYSTEM : System Diagram
INFOID:0000000006220164
POWER CONTROL SYSTEM : System DescriptionINFOID:0000000006220165
COOLING FAN CONTROL
IPDM E/R outputs cooling fan control signal (PWM signal ) to the electrically-controlled cooling fan coupling
according to the status of the cooling fan speed request signal received from ECM via CAN communication.
Refer to EC-41, "
COOLING FAN CONTROL : System Diagram".
ALTERNATOR CONTROL
IPDM E/R outputs power generation command signal (PWM signal ) to the alternator according to the status of
the power generation command value signal received from ECM via CAN communication. Refer to CHG-7,
"POWER GENERATION VOLTAGE VARIABLE CONTROL SYSTEM : System Diagram".
SIGNAL BUFFER SYSTEM
SIGNAL BUFFER SYSTEM : System DiagramINFOID:0000000006220166
SIGNAL BUFFER SYSTEM : System DescriptionINFOID:0000000006220167
 IPDM E/R reads the status of the oil pressure switch and transmits the oil pressure switch signal to BCM via
CAN communication. Refer to MWI-15, "
OIL PRESSURE WARNING LAMP : System Diagram".
 IPDM E/R reads the status of the hood switch and tr ansmits the hood switch signal to BCM via CAN commu-
nication. Refer to SEC-17, "
VEHICLE SECURITY SYSTEM : System Diagram".
 IPDM E/R receives the rear window defogger control signal from BCM via CAN communication and trans- mits it to ECM and AV control unit via CAN communication. Refer to DEF-6, "
System Diagram".
POWER CONSUMPTION CONTROL SYSTEM
JMMIA0491GB
JPMIA0952GB
Revision: 2010 May2011 QX56

PCS-18
< ECU DIAGNOSIS INFORMATION >[IPDM E/R]
IPDM E/R
17
(B) Ground Cooling fan motor
ground
Output Ignition switch ON 0 V
18
(B) Ground Ground — Ignition switch ON 0 V
19
(V) Ground Front fog lamp (RH) Output Lighting
switch 2ND or
AUTO (Light
is illuminated)Front fog lamp switch
OFF
0 V
Front fog lamp switch ON Battery voltage
20
(W) Ground Front fog lamp (LH) Output Lighting
switch 2ND or
AUTO (Light
is illuminated)Front fog lamp switch
OFF
0 V
Front fog lamp switch ON Battery voltage
21
(L) Ground
Headlamp washer re-
lay control Output
Ignition switch
ON Headlamp washer acti-
vated
0 V
Headlamp washer deacti-
vated 12 V
23
(GR/R) Ground Cranking request Output Select lever P or N (Ignition switch ON) 0 V
Select lever in any position other than P or
N (Ignition switch ON)
12 V
Engine running 12 V
24
(W/G) Ground Oil pressure switch Input Ignition switch
ONEngine stopped 0 V
Engine running 12 V
25
(L/Y) Ground Front wiper stop posi-
tion InputIgnition switch
ON Front wiper stop position 0 V
Any position other than
front wiper stop position
12 V
26
(P) Ground CAN-L Input/
Output ——
27
(L) Ground CAN-H
Input/
Output ——
30
(R/W) Ground Starter relay control Output  Ignition switch OFF or ACC
 At engine cranking
0 V
 Ignition switch ON
 Engine running 12 V
31
(B) Ground Injector relay control Output  Approximately 1 second after turning
the ignition switch ON
 Engine running 0 - 1.5 V
Approximately 1 second or more after turn-
ing the ignition switch ON Battery voltage
32
(LG) Ground Hood switch Input Close the hood 12 V
Open the hood 0 V
33
(R) Ground Alternator control Output Ignition switch OFF or ACC 0 V
Ignition switch ON 6 V
34
(P/B) Ground Horn relay control Output The horn is deactivated Battery voltage
The horn is activated 0 V
Te r m i n a l N O .
(Wire color) Description
Condition Va l u e
(Approx.)
Signal name Input/
Output
+–
Revision: 2010 May2011 QX56

PCS
IPDM E/RPCS-21
< ECU DIAGNOSIS INFORMATION > [IPDM E/R]
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Fail-SafeINFOID:0000000006220173
CAN COMMUNICATION CONTROL
When CAN communication with ECM and BCM is impossible,
IPDM E/R performs fail-safe control. After CAN
communication recovers normally, it also returns to normal control.
If No CAN Communication Is Available With ECM
If No CAN Communication Is Available With BCM
66
(SB) Ground
Push-button ignition
switch InputPress the push-button ignition switch 0 V
Release the push-button ignition switch 12 V
68
(O) Ground Ignition relay monitor Input Ignition switch OFF or ACC 12 V
Ignition switch ON 0 V
69
(W/B) Ground Ignition power supply Output Ignition switch OFF or ACC 0 V
Ignition switch ON Battery voltage
72
(Y/R) Ground Cooling fan control Output Ignition switch
OFF 5 V
ACC 0 V
ON
2. 5 V
Engine running
Te r m i n a l N O .
(Wire color) Description
Condition Va l u e
(Approx.)
Signal name Input/
Output
+–
JMMIA0404GB
Control part Fail-safe operation
Cooling fan  Transmits the pulse duty signal (PWM signal) 100% when the ignition switch is turned ON.
 Transmits the pulse duty signal (PWM signal)
0% when the ignition switch is turned OFF.
A/C compressor A/C relay OFF
Alternator Transmits the power generation command signal (PWM signal) 0%
Control part Fail-safe operation
Headlamp  Turns ON the headlamp low relay when the ignition switch is turned ON
 Turns OFF the headlamp low relay when the ignition switch is turned OFF
 Headlamp high relay OFF
Parking lamp
 License plate lamp
 Illumination
 Tail lamp
 Side marker lamp  Turns ON the tail lamp relay when the ignition switch is turned ON
 Turns OFF the tail lamp relay when the ignition switch is turned OFF
Front wiper motor  The status just before activation of fail-safe control is maintained until the ignition switch is
turned OFF while the front wiper is operating at LO or HI speed.
 The wiper is operated at LO speed until the ignition switch is turned OFF if the fail-safe con-
trol is activated while the front wiper is set in the INT mode and the front wiper motor is op-
erating.
 Return automatically wiper to stop position when ignition switch is turned ON if fail-safe con-
trol is activated while front wiper motor is operated and wiper stops in the other position than
stop position.
Front fog lamp Front fog lamp relay OFF
Horn Horn OFF
Revision: 2010 May2011 QX56