ESP INFINITI QX56 2011 Factory Repair Manual

EC-444
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1572 ICC BRAKE SWITCH
Always drive vehicle at a safe speed.
NOTE:
This procedure may be conducted with the drive wheel
s lifted in the shop or by driving the vehicle.
If a road test is expected to be easier , it is unnecessary to lift the vehicle.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-444, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217948
1.CHECK DTC WITH ADAS CONTROL UNIT
Refer to DAS-21, "
CONSULT-III Function (ICC/ADAS)" and DAS-38, "DTC Index".
Are any DTCs detected?
YES >> Perform the Diagnosis Procedure corresponding to the detected DTC.
NO >> GO TO 2.
2.CHECK OVERALL FUNCTION-I
WITH CONSULT-III
1. Turn ignition switch ON.
2. Select “BRAKE SW1” in “DAT A MONITOR” mode with CONSULT-III.
3. Check “BRAKE SW1” indication under the following conditions.
WITHOUT CONSULT-III
1. Turn ignition switch ON.
2. Check the voltage between ECM harness connector terminals under the following conditions.
Is the inspection result normal?
YES >> GO TO 8.
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.
Vehicle speed More than 30 km/h (19 mph)
Selector lever Suitable position
Driving location Depress the brake pedal for more than 5 seconds so as
not to come off from the above-mentioned vehicle speed.
Monitor item Condition Indication
BRAKE SW1
(ICC brake switch) Brake pedalSlightly depressed OFF
Fully released ON
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 1 Ground Battery voltage
Revision: 2010 May2011 QX56

EC-448
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1574 ASCD VEHICL
E SPEED SENSOR
YES >> GO TO 2.
NO >> Perform Diagnosis Procedure corresponding to the DTC indicated.
2.CHECK DTC WITH “ABS ACTUATOR A ND ELECTRIC UNIT (CONTROL UNIT)”
Refer to BRC-40, "
CONSULT-III Function".
Is the inspection result normal?
YES >> GO TO 3.
NO >> Perform Diagnosis Procedure corresponding to the DTC indicated.
3.CHECK DTC WITH “COMBINATION METER”
Refer to MWI-30, "
CONSULT-III Function".
>> INSPECTION END
Revision: 2010 May2011 QX56

EC-450
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1574 ICC VEHICLE SPEED SENSOR
NO >> Perform Diagnosis Procedure corresponding to the DTC indicated.
2.CHECK DTC WITH “ABS ACTUATOR A
ND ELECTRIC UNIT (CONTROL UNIT)”
Refer to BRC-40, "
CONSULT-III Function".
Is the inspection result normal?
YES >> GO TO 3.
NO >> Perform Diagnosis Procedure corresponding to the DTC indicated.
3.CHECK DTC WITH “COMBINATION METER”
Check combination meter function.
Refer to MWI-30, "
CONSULT-III Function".
>> INSPECTION END
Revision: 2010 May2011 QX56

EC-460
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P2101 ELECTRIC THROTTLE CONTROL FUNCTION
P2101 ELECTRIC THROTTL
E CONTROL FUNCTION
DescriptionINFOID:0000000006217962
Electric throttle control actuator consists of th rottle control motor, throttle position sensor, etc.
The throttle control motor is operated by the ECM and it opens and closes the throttle valve.
The current opening angle of the throttle valve is detected by the throttle position sensor and it provides feed-
back to the ECM. ECM controls the throttle valve openi ng angle in response to driving condition via the throttle
control motor.
DTC LogicINFOID:0000000006217963
DTC DETECTION LOGIC
NOTE:
 If DTC P2101 is displayed with DTC P2100, first pe rform the trouble diagnosis for DTC P2100. Refer
to EC-458, "
DTC Logic".
 If DTC P2101 is displayed with DTC P2119, first pe rform the trouble diagnosis for DTC P2119. Refer
to EC-466, "
DTC Logic".
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is 11 V or more at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON and wait at least 2 seconds.
2. Start engine and let it idle for 5 seconds.
3. Check DTC.
Is DTC detected?
YES >> Go to EC-460, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217964
1.CHECK THROTTLE CONTROL MOTOR RELAY INPUT SIGNAL CIRCUIT-I
1. Check the voltage between ECM harness connector and ground under the following conditions.
Is the inspection result normal?
YES >> GO TO 8.
NO >> GO TO 2.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2101 Electric throttle control
performance Electric throttle control function does not
operate properly.  Harness or connectors
(Throttle control motor circuit is open or shorted)
 Electric throttle control actuator
ECM Ground Condition Voltage
Connector Terminal
E80 173 Ground Ignition switch:
OFF
Approx. 0 V
Ignition switch:
ON Battery voltage
Revision: 2010 May2011 QX56

ICC BRAKE SWITCHEC-503
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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ICC BRAKE SWITCH
Component Function CheckINFOID:0000000006218008
1.CHECK ICC BRAKE SWITCH FUNCTION
WITH CONSULT-III
1. Turn ignition switch ON.
2. Select “BRAKE SW1” in “DATA MONITOR” mode with CONSULT-III.
3. Check “BRAKE SW1” indication under the following conditions.
WITHOUT CONSULT-III
1. Turn ignition switch ON.
2. Check the voltage between ECM harness connector terminals as per the following.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC-503, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006218009
1.CHECK DTC WITH ADAS CONTROL UNIT
Refer to DAS-21, "
CONSULT-III Function (ICC/ADAS)" and DAS-38, "DTC Index".
Are any DTCs detected?
YES >> Perform the Diagnosis Procedur e corresponding to the detected DTC.
NO >> GO TO 2.
2.CHECK OVERALL FUNCTION
WITH CONSULT-III
1. Turn ignition switch ON.
2. Select “BRAKE SW1” in “DATA MONITOR” mode with CONSULT-III.
3. Check “BRAKE SW1” indication under the following conditions.
WITHOUT CONSULT-III
1. Turn ignition switch ON.
2. Check the voltage between ECM harness connector terminals under the following conditions.
Monitor item Condition Indication
BRAKE SW1
(ICC brake switch) Brake pedalSlightly depressed OFF
Fully released ON
ECM
Condition Voltage
Connector +–
Terminal Terminal
E80 147
(ICC brake switch signal) 175 Brake pedalSlightly depressed Approx. 0 V
Fully released Battery voltage
Monitor item Condition Indication
BRAKE SW1
(ICC brake switch) Brake pedalSlightly depressed OFF
Fully released ON
Revision: 2010 May2011 QX56

EM-16
< BASIC INSPECTION >
COMPRESSION PRESSURE
COMPRESSION PRESSURE
InspectionINFOID:0000000006289521
1. Warm up engine thoroughly. Then, stop it.
2. Release fuel pressure. Refer to EC-153, "
Work Procedure".
CAUTION:
If CONSULT-III is not used to release fuel pr essure leave the fuel pump fuse disconnected until
step 7.
3. Remove fuel pump fuse in IPDM E/R. NOTE:
 For the fuse number, refer to EC-114, "
Wiring Diagram".
 For the fuse arrangement, refer to PG-143, "
Fuse, Connector and Terminal Arrangement".
4. Remove engine cover. Refer to EM-25, "
Exploded View".
5. Remove ignition coil and spark plug from each cylinder. Refer to EM-29, "
Exploded View".
6. Connect engine tachometer (not required in use of CONSULT-III).
7. Install the compression tester with Tool [SST: EG15050500 (J- 45402)] into the spark plug hole.
8. Measure compression pressure using compressi on gauge connected with flexible type adapter (commer-
cial service tool).
9. With accelerator pedal fully depressed, turn ignition switch to “START” for cranking. When the gauge pointer stabilizes, read the compression pressure and the engine rpm. Perform these steps to check each
cylinder.
CAUTION:
 Measure a six-cylinder under the same conditio ns since a measurement depends on measure-
ment conditions (engine water temperature, etc.).
 Always use a fully changed battery to obtain the specified engine speed.
 If the engine speed is out of the specified range, c heck battery liquid for proper gravity. Check the
engine speed again with normal battery gravity. Refer to PG-159, "
How to Handle Battery".
 If compression pressure is below the minimum value, check valve clearances and parts associated with combustion chamber (valve, valve seat, piston, pi ston ring, cylinder bore, cylinder head, cylinder head
gasket). After checking, measure compression pressure again.
 If a cylinder has low compression pressure, pour a small amount of engine oil into the spark plug hole of the cylinder to re-check it for compression.
- If the added engine oil improves the compression, pi ston rings may be worn out or damaged. Check pis-
ton rings and replace if necessary. Refer to EM-107, "
Disassembly and Assembly".
- If the compression pressure remains at low level despite the addition of engine oil, valves may be mal- functioning. Check valves for damage. Replace valve or valve seat accordingly. Refer to EM-107, "
Dis-
assembly and Assembly".
 If two adjacent cylinders have respectively low co mpression pressure and their compression remains
low even after the addition of engine oil, cylinder head gaskets are leaking. In such a case, replace cyl-
inder head gaskets. Refer to EM-87, "
Removal and Installation".
10. After inspection is completed, install removed parts.
11. Start the engine, and check that the engine runs smoothly.
WBIA0605E
Compression pressure : Refer to EM-132, "GeneralSpecification".
Revision: 2010 May2011 QX56

EM-44
< REMOVAL AND INSTALLATION >
HIGH PRESSURE FUEL PUMP AND FUEL HOSE
4. Remove fuel feed tube (pump side) (1).
5. Disconnect fuel hose (2) from high pressure fuel pump.
6. Remove high pressure fuel pump and lifter.CAUTION:
After removing lifter, replace lifter with a new one.
7. Disconnect quick connector (A) with the following procedure.
a. Remove quick connector cap from quick connector connection.
b. With the sleeve side of quick connector release facing quick connector, install quick connector release
onto fuel tube.
c. Insert quick connector release into quick connector until sleeve contacts and goes no further. Hold quick connector release on
that position.
CAUTION:
Inserting quick connector re lease hard will not disconnect
quick connector. Hold qui ck connector release where it
contacts and goes no further.
d. Draw and pull out quick connector straight from fuel tube. CAUTION:
 Pull quick connector holding (A) position as shown in thefigure.
 Never pull with lateral force applied. O-ring inside quick
connector may be damaged.
 Prepare container and cloth befo rehand because fuel will leak out.
 Avoid fire and sparks.
 Keep parts away from heat source. Especially, be careful when welding is performed around
them.
 Never expose parts to battery electrolyte or other acids.
 Never bend or twist connection between quick c onnector and fuel feed hose (with damper) dur-
ing installation/removal.
JPBIA3479ZZ
JPBIA3493ZZ
KBIA0702E
Revision: 2010 May2011 QX56

EM-66
< REMOVAL AND INSTALLATION >
TIMING CHAIN
NOTE:
 The above figure shows the relationship between the matching mark on each timing chain and that on the
corresponding sprocket, with the components installed.
 Parts with an identification mark (R or L) should be installed on the corresponding bank according to the
mark.
- Intake camshaft sprocket, exhaust camshaft sprocket
- Tension guide
- Slack guide
 To install timing chain and related parts, start with those on bank 2. The procedure for installing parts on
bank 1 is omitted because it is the same as that for installation on bank 2.
1. High pressure fuel pump camshaft 2. Intake camshaft sprocket (bank 2) 3. Exhaust camshaft sprocket (bank 2)
4. Timing chain (bank 2) 5. Slack guide (bank 2) 6. Chain oil jet (bank 2)
7. Timing chain tensioner (bank 2) 8. Crankshaft sprocket (bank 2 side) 9. Crankshaft sprocket (bank 1 side)
10. Chain oil jet (bank 1) 11. Tension guide (bank 1) 12. Timing chain (bank 1)
13. Exhaust camshaft sprocket (bank 1) 14. Intake camshaft sprocket (bank 1) 15. Timing chain tensioner (bank 1)
16. Slack guide (bank 1) 17. Tension guide (bank 2) 18. Dowel pin
A: Matching mark (copper link) B: Matching mark (punched) C: Matching mark (outer groove)
D: Matching mark (white link) E. Matching mark (notched) F. Matching mark (yellow link)
G. Crankshaft key
JPBIA3482ZZ
Revision: 2010 May2011 QX56

EM-84
< REMOVAL AND INSTALLATION >
CAMSHAFT
 Move control shaft (A) to the small stopper and large stopper tocheck that the control shaft functions smoothly.
CAUTION:
Turn VVEL ladder assembly upside down to prevent the drive
shaft from dropping off.
RINK CHECK FOR BACK-LASH (BONDING) Check that the link and the shaft of drive shaft and control shaft are
not fixed.
 Check this by moving drive shaft and control shaft in the axial and
rotation directions.
 If there is an unusualness related to the above three items, replace VVEL ladder assembly & cylinder head
assembly.
NOTE:
VVEL ladder assembly cannot be replaced as a singl e part, because it is machined together with cylinder
head assembly.
INSPECTION AFTER ASSEMBLY
Inspection of Camshaft Sprocket (INT) Oil Groove
CAUTION:
 Perform this inspection only when DTC P0011, P 0021 are detected in self-diagnostic results of CON-
SULT-III and it is directed according to inspection procedure of EC section. Refer to EC-177, "
DTC
Logic".
 Check when engine is cold to prevent burns from the splashing engine oil.
1. Check engine oil level. Refer to LU-7, "
Inspection".
2. Perform the following procedure to prevent the engine from being unintentionally started while checking.
a. Release the fuel pressure. Refer to EC-153, "
Work Procedure".
b. Disconnect ignition coil and injector harness connectors.
3. Remove valve timing control solenoid valve. Refer to EM-61, "
Exploded View".
4. Crank engine, and then check that engine oil comes out from valve timing control solenoid valve hole (A). End crank after
checking.
WARNING:
Be careful not to touch rotati ng parts (drive belt, idler pul-
ley, and crankshaft pulley, etc.).
CAUTION:
 Prevent splashing by using a shop cloth to prevent the worker from injury from en gine oil and to prevent engine
oil contamination.
 Prevent splashing by using a shop cloth to prevent engine oil from being splashed to engine and
vehicle. Especially, be careful not to apply engine oil to rubber parts of drive belt, engine mount-
ing insulator, etc. Wipe engine oil out immediately if it is splashed.
: Engine front
JPBIA3521ZZ
JPBIA3522ZZ
1 : Valve timing control cover (bank 2)
JPBIA3523ZZ
Revision: 2010 May2011 QX56

CYLINDER BLOCKEM-107
< UNIT DISASSEMBLY AND ASSEMBLY >
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Disassembly and AssemblyINFOID:0000000006289583
DISASSEMBLY
1. Remove the following parts:
 Oil pans (lower and upper): Refer to EM-54, "
Exploded View" and EM-57, "Exploded View".
 Front cover and timing chain: Refer to EM-61, "
Exploded View".
 Cylinder head: Refer to EM-86, "
Exploded View".
2. Remove knock sensor. CAUTION:
Carefully handle knock sensor avoiding shocks.
3. Remove oil filter (for VVEL ladder assembly ) from cylinder block, if necessary. Refer to EM-86, "
Exploded
View".
4. Remove piston and connecting rod assembly as per the following:  Before removing piston and connecting rod assembly, check the connecting rod side clearance. Refer to
EM-115, "
Inspection".
CAUTION:
Be careful not to drop connecting r od bearing, and to scratch the surface.
a. Position crankshaft pin corresponding to connecting rod to be removed onto the bottom dead center.
b. Loosen mounting bolts, and remove connecting rod bearing cap.
c. Using a hammer handle (A) or similar tool, push piston and con- necting rod assembly out to the cylinder head side.
CAUTION:
Be careful not to damage the cylinder wall and crankshaft
pin, resulting from an interf erence of the connecting rod big
end.
5. Remove connecting rod bearings from connecting rod and connecting rod bearing cap.
CAUTION:
 Be careful not to drop connecting rod bearing, and to scratch the surface.
 Identify installation positions, and store them without mixing them up.
6. Remove piston rings from piston.  Before removing piston rings, check the piston ring side clearance. Refer to EM-115, "
Inspection".
10. Main bearing cap sub bolt 11. Main bearing cap bolt 12. Connecting rod cap bolt
13. Connecting rod cap 14. Connecting rod bearing 15. Connecting rod
16. Snap ring 17. Piston pin 18. Piston
19. Oil ring 20. Second ring 21. Top ring
22. Pilot converter 23. Drive plate 24. Reinforcement plate
25. Rear oil seal 26. Rear oil seal retainer 27. O-ring
28. Crankshaft position sensor (POS) 29. Cylinder block heater (for Canada)
A.Comply with the assembly procedure
when tightening. Refer to
EM-107
.B. Chamfered C. Installed on transmission
: Crankshaft side
Refer to GI-4, "
Components" for symbol marks in the figure.
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Revision: 2010 May2011 QX56