air condition INFINITI QX56 2011 Factory Service Manual

EC-502
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
HIGH PRESSURE FUEL PUMP
4. Also check harness for short to ground and to power.
Is inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace error-detected parts.
2.CHECK HIGH PRESSURE
FUEL PUMP SOLENOID
Refer to EC-502, "
Component Inspection".
Is inspection result normal?
YES >> GO TO 3.
NO >> Replace high pressure fuel pump. Refer to EM-43, "
Removal and Installation".
3.CHECK HIGH PRESSURE FUEL PUMP INSTALLATION CONDITION
1. Turn ignition switch OFF.
2. Check that the high pressure fuel pump is installed with no backlash and looseness.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair or replace error-detected parts.
4.CHECK CAMSHAFT
1. Remove camshaft. Refer to EM-75, "
Removal and Installation".
2. Check camshaft. Refer to EM-77, "
Inspection".
Is inspection result normal?
YES >> INSPECTION END
NO >> Replace camshaft. Refer to EM-75, "
Removal and Installation".
Component InspectionINFOID:0000000006218007
1.CHECK HIGH PRESSURE FUEL PUMP SOLENOID
1. Turn ignition switch OFF.
2. Disconnect high pressure fuel pump harness connector.
3. Check the resistance between high pressure fuel pump connector terminals as per the following.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace high pressure fuel pump. Refer to EM-43, "
Removal and Installation".
+−
Condition Resistance
High pressure fuel pump
Te r m i n a l
1 2 Temperature 20 – 30 °C (68 – 86 °F) 9 – 11 Ω
Revision: 2010 May2011 QX56

EC-504
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
ICC BRAKE SWITCH
Is the inspection result normal?
YES >> INSPECTION END
NO >> GO TO 3.
3.CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF.
2. Disconnect ICC brake switch harness connector.
3. Turn ignition switch ON.
4. Check the voltage between ICC brake switch harness connector and ground.
Is the inspection result normal?
YES >> GO TO 7.
NO >> GO TO 4.
4.CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT-II
Check the voltage between ICC brake switch harness connector and ground.
Is the inspection result normal?
YES >> GO TO 6.
NO >> GO TO 5.
5.DETECT MALFUNCTIONING PART
Check the following.
 Fuse block (J/B) connector E103
 10 A fuse (No. 3)
 Harness for open or short between ICC brake switch and fuse
>> Repair open circuit or short to ground in harness or connectors.
6.CHECK ICC BRAKE SWITCH
Refer to EC-445, "
Component Inspection (ICC Brake Switch)".
Is the inspection result normal?
YES >> GO TO 9.
NO >> Replace ICC brake switch. Refer to BR-20, "
Removal and Installation".
7.CHECK ICC BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the continuity between ICC brake s witch harness connector and ECM harness connector.
ECM
Condition Voltage (V)
Connector +–
Te r m i n a l Te r m i n a l
E80 147
(ICC brake switch signal) 175 Brake pedalSlightly depressed Approx. 0
Fully released Battery voltage
ICC brake switch
Ground Voltage
Connector Terminal
E68 2 Ground Battery voltage
ICC brake switch Ground Voltage
Connector Terminal
E68 1 Ground Battery voltage
Revision: 2010 May2011 QX56

ICC BRAKE SWITCHEC-505
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 9.
NO >> GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the following.
 Harness for open or short between ICC brake switch and ECM
 Loose or poor connection for each connector and harness
>> Repair open circuit, short to ground or short to power in harness or connectors.
9.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Component Inspection (ICC Brake Switch)INFOID:0000000006218010
1.CHECK ICC BRAKE SWITCH-I
1. Turn ignition switch OFF.
2. Disconnect ICC brake switch harness connector.
3. Check the continuity between ICC brake switch terminals under the following conditions.
Is the inspection result normal?
YES >> INSPECTION END
NO >> GO TO 2.
2.CHECK ICC BRAKE SWITCH-II
1. Adjust ICC brake switch installation. Refer to BR-21, "
Inspection and Adjustment".
2. Check the continuity between ICC brake switch terminals under the following conditions.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace ICC brake switch. Refer to BR-20, "
Removal and Installation".
ICC brake switch ECM
Continuity
Connector Terminal Connector Terminal
E68 2 E80 147 Existed
Terminals Condition Continuity
1 and 2 Brake pedal Fully released Existed
Slightly depressed Not existed
Terminals Condition Continuity
1 and 2 Brake pedal Fully released Existed
Slightly depressed Not existed
Revision: 2010 May2011 QX56

LOW PRESSURE FUEL PUMPEC-513
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
YES >> GO TO 4.
NO >> Repair or replace error-detected parts.
4.CHECK FUEL PUMP CONTROL CIRCUIT
1. Disconnect fuel level sensor unit and fuel pump harness connector.
2. Check the continuity between FPCM harness connecto r and fuel level sensor unit and fuel pump harness
connector.
3. Also check harness for short to ground and to power.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair or replace error-detected parts.
5.CHECK LOW PRESSURE FUEL PUMP
Refer to EC-513, "
Component Inspection (Low Pressure Fuel Pump)".
Is the inspection result normal?
YES >> GO TO 6.
NO >> Replace fuel level sensor unit and fuel pump. Refer to FL-5, "
Removal and Installation".
6.CHECK FPCM
Refer to EC-514, "
Component Inspection (FPCM)".
Is the inspection result normal?
YES >> Check intermittent incident. Refer to GI-40, "Intermittent Incident".
NO >> Replace FPCM. Refer to EC-537, "
Removal and Installation".
Component Inspection (Low Pressure Fuel Pump)INFOID:0000000006218019
1.CHECK FUEL PRESSURE REGULATOR
1. Turn ignition switch OFF.
2. Check low fuel pressure. Refer to EC-153, "
Work Procedure".
Is inspection result normal?
YES >> INSPECTION END
NO >> GO TO 2.
2.CHECK LOW PRESSURE FUEL PUMP
1. Turn ignition switch OFF.
2. Disconnect fuel level sensor unit and fuel pump.
3. Check resistance between fuel level sens or unit and fuel pump terminals as follows.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace fuel level sensor unit and fuel pump. Refer to FL-5, "
Removal and Installation".
+−
Continuity
FPCM Fuel level sensor unit and fuel pump
Connector Terminal Connector Terminal
B41 6
C5 3
Existed
71
+ −
Condition Resistance
Fuel level sensor unit and fuel
pump
Te r m i n a l s
1 3 Temperature: 25 °C (77 °F) 0.2 - 5.0 Ω
Revision: 2010 May2011 QX56

EC-522
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
SNOW MODE SWITCH
SNOW MODE SWITCH
DescriptionINFOID:0000000006256403
The snow mode switch signal is sent to the combinat
ion meter from the snow mode switch. The combination
meter then sends the signal to the ECM via the CAN communication line.
The snow mode is used for driving or starting the vehicle on snowy roads or slippery areas. If the snow mode
is activated, the vehicle speed will not accelerate as quickly as normal to avoid vehicle slip. In other words,
ECM controls rapid engine torque change by controlling t he electric throttle control actuator operating speed.
Component Function CheckINFOID:0000000006256404
1.CHECK SNOW MODE SWITCH FUNCTION
1. Turn ignition switch ON.
2. Select “SNOW MODE SW” in “DATA MONITOR” mode with CONSULT-III.
3. Check “SNOW MODE SW” indication under the following conditions.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC-522, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006256405
1.CHECK DTC WITH COMBINATION METER
Refer to MWI-30, "
CONSULT-III Function".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Go to MWI-57, "
Work flow".
2.CHECK SNOW MODE SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect snow mode switch harness connector.
3. Turn ignition switch ON.
4. Check the voltage between snow mode switch harness connector and ground.
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
3.DETECT MALFUNCTIONING PART
Check the following.
 Fuse block harness connector M3
 10 A fuse (No. 13)
 Harness for open or short between snow mode switch and fuse.
>> Repair open circuit, short to ground or short to power in harness or connectors.
4.CHECK SNOW MODE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
Monitor item Condition Indication
SNOW MODE SW Snow mode switch ON ON
OFF OFF
Snow mode switch
Ground Voltage
Connector Terminal
M54 12 Ground Battery voltage
Revision: 2010 May2011 QX56

SNOW MODE SWITCHEC-523
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
2. Disconnect combination meter harness connector.
3. Check the continuity between snow mode switch
harness connector and combination meter harness con-
nector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair open circuit, short to ground or short to power in harness or connector.
5.CHECK SNOW MODE SWITCH
Refer to EC-523, "
Component Inspection".
Is the inspection result normal?
YES >> GO TO 6.
NO >> Replace snow mode switch. Refer to IP-25, "
Removal and Installation".
6.CHECK INTERMITTENT INCIDENT
Refer to GI-40, "
Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000006256406
1.CHECK SNOW MODE SWITCH
1. Turn ignition switch OFF.
2. Disconnect snow mode s witch harness connector.
3. Check the continuity between snow mode s witch terminals under the following conditions.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace snow mode switch. Refer to IP-25, "
Removal and Installation".
Snow mode switch Combination meter
Continuity
Connector Terminal Connector Terminal
M54 22 M34 33 Existed
Terminals Condition Continuity
12 and 22 Snow mode switch ON Existed
OFF Not Existed
Revision: 2010 May2011 QX56

ENGINE CONTROL SYSTEM SYMPTOMSEC-525
< SYMPTOM DIAGNOSIS > [VK56VD]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
Mass air flow sensor circuit
1
12 2
222 2 EC-201
Engine coolant temperature sensor circuit
333
EC-217
Air fuel ratio (A/F) sensor 1 circuit EC-181
EC-228
EC-232
EC-235
EC-238
Throttle position sensor circuit
22EC-219
EC-288
EC-406
EC-407
EC-475
Accelerator pedal position sensor circuit 3 2 1
EC-468EC-471
EC-478
Knock sensor circuit 2 3
EC-297
Engine oil temperature sensor 4 2 3EC-285
Crankshaft position sensor circuit 2 2EC-299
Camshaft position sensor circuit 3 2EC-303
Vehicle speed signal circuit 2 3 3 3EC-356
Power steering pressure sensor circuit 2 3 3EC-371
ECM 22333333333EC-376EC-378
EC-380
Intake valve timing control solenoid valve cir-
cuit
32 13223 3
EC-193
VVEL control module 3 4 4 3 EC-451EC-452
VVEL actuator motor 3 4 4 3
EC-390
VVEL actuator motor relay 3 4 4 3EC-393
VVEL control shaft position sensor 3 4 4 3EC-387
PNP signal circuit 3 3 3 3 3EC-383
Refrigerant pressure sensor circuit 2 3 3 4EC-520
Electrical load signal circuit 3EC-493
Air conditioner circuit 223333333 3 2HAC-60
ABS actuator and electric unit (control unit) 4BRC-60
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Revision: 2010 May2011 QX56

EC-538
< SERVICE DATA AND SPECIFICATIONS (SDS) [VK56VD]
SERVICE DATA AND SPECIFICATIONS (SDS)
SERVICE DATA AND SPECIFICATIONS (SDS)
SERVICE DATA AND SPECIFICATIONS (SDS)
Idle SpeedINFOID:0000000006218038
*: Under the following conditions
 A/C switch: OFF
 Electric load: OFF (Lights, heater fan & rear window defogger)
 Steering wheel: Kept in straight-ahead position
Ignition TimingINFOID:0000000006218039
*: Under the following conditions
 A/C switch: OFF
 Electric load: OFF (Lights, heater fan & rear window defogger)
 Steering wheel: Kept in straight-ahead position
Calculated Load ValueINFOID:0000000006218040
Mass Air Flow SensorINFOID:0000000006218041
*: Engine is warmed up to normal operating temperature and running under no load.Condition Specification
No load* (in P or N position) 600 ± 50 rpm
Condition Specification
No load* (in P or N position) 12 ± 2 °BTDC
Condition Specification (U sing CONSULT-III or GST)
At idle 5 – 35%
At 2,500 rpm 5 – 35%
Supply voltageBattery voltage (11 – 14 V)
Output voltage at idle 0.9 – 1.1 V*
Mass air flow (Using CONSULT-III or GST) 1.0 – 5.0 g/s at idle*
7.0 – 20.0 g/s at 2,500 rpm*
Revision: 2010 May2011 QX56

EM-10
< PREPARATION >
PREPARATION
(—)
Pilot bushing pullerRemoving pilot converter
(—)
Valve seat cutter set Finishing valve seat (EXH) dimensions
(—)
Piston ring expander Removing and installing piston ring
(—)
Valve guide drift Removing and installing valve guide (EXH)
a: 9.5 mm (0.374 in) dia.
b: 5.5 mm (0.217 in) dia.
(—)
Valve guide reamer (A): Reaming valve guide (EXH) inner hole
(B): Reaming hole for oversize valve guide
(EXH)
c: 6.0 mm (0.236 in) dia.
d: 10.2 mm (0.402 in) dia.
(J-43897-18)
(J-43897-12)
Oxygen sensor thread cleaner Reconditioning the exhaust system threads be-
fore installing a new heated oxygen sensor (Use
with anti-seize lubricant shown below.)
a: J-43897-18 (18 mm dia.) for zirconia heat-
ed oxygen sensor and air fuel ratio sensor

b: J-43897-12 (12 mm dia.) for titania heated
oxygen sensor and air fuel ratio sensor
(—)
Anti-seize lubricant (Permatex 133AR
or equivalent meeting MIL specifica-
tion MIL-A-907) Lubricating oxygen sensor thread cleaning tool
when reconditioning exhaust system threads
(Kent-Moore No.)
Tool name
Description
NT045
S-NT048
S-NT030
JPBIA0400ZZ
JPBIA0401ZZ
AEM488
AEM489
Revision: 2010 May2011 QX56

NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTINGEM-19
< SYMPTOM DIAGNOSIS >
C
DE
F
G H
I
J
K L
M A
EM
NP
O
Use the Chart Below to Help You Find the Cause of the SymptomINFOID:0000000006289523
1. Locate the area where noise occurs.
2. Confirm the type of noise.
3. Specify the operating condition of the engine.
4. Check specified noise source.
If necessary, repair or replace these parts.
A: Closely related B: Related C: Sometimes related —: Not related Location
of noise Type of
noise Operating condition of engine
Source of noise Check item Refer-
ence page
Before
warm- up After
warm- up When
start- ing When
idling When
racing While
driving
Top of en-
gine
Rocker
cover
Cylinder
head Ticking or
clicking
CA—AB— Tappet
noiseValve clearance
EM-12
Rattle C A — A B C Camshaft
bearing
noiseCamshaft runout
Camshaft journal oil
clearance
EM-77
Crank-
shaft pul-
ley
Cylinder
block
(Side of
engine)
Oil panSlap or
knock
—A—B B—
Piston pin
noisePiston to piston pin oil
clearance
Connecting rod bushing
oil clearance
EM-115
Slap or
rap
A——B B A
Piston
slap noisePiston to cylinder bore
clearance
Piston ring side clear-
ance
Piston ring end gap
Connecting rod bend
and torsion
EM-115
Knock A B C B B B
Connect-
ing rod
bearing
noiseConnecting rod bushing
oil clearance
Connecting rod bearing
oil clearance
EM-115
Knock A B — A B C
Main bear-
ing noiseMain bearing oil clear-
ance
Crankshaft runout
EM-115
Front of
engine
Timing
chain caseTapping or
ticking
AA—BBB Timing
chain and
timing
chain ten-
sioner
noiseTiming chain cracks
and wears
Timing chain tensioner
operation
EM-72
Front of
engineSqueak-
ing or fizz-
ing
AB—B—C Drive belts
(Sticking
or slip-
ping)Drive belts deflection
EM-20
CreakingABABAB Drive belts
(Slipping)Idler pulley bearing op-
eration
Squall
Creak AB—BAB Water
pump
noiseWater pump operation
CO-19
Revision: 2010 May2011 QX56