TROUBLE DIAGNOSIS
EC-107
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1 - 6: The numbers refer to the order of inspection.Exhaust Exhaust manifold/Tube/Muffler/
Gasket
55555 55 5EM-19
, EX-
3Three way catalyst
Lubrica-
tionOil pan/Oil strainer/Oil pump/Oil
filter/Oil gallery/Oil cooler
55555 55 5EM-22
, LU-
13 , LU-10 ,
LU-11
Oil level (Low)/Filthy oilLU-7
Cooling Radiator/Hose/Radiator filler cap
55555 55 45CO-12
Thermostat 5CO-19
Water pum pCO-17
Water galleryCO-8
Cooling fan 5CO-15
Coolant level (Low)/Contami-
nated coolant5CO-10
IVIS (INFINITI Vehicle Immobilizer System —
NATS)11BL-137
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
TROUBLE DIAGNOSIS
EC-127
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ENGINE CONTROL COMPONENT PARTS/CONTROL SYSTEMS APPLICATION
ItemDIAGNOSTIC TEST MODE
WORK
SUP-
PORTSELF-DIAGNOSTIC
RESULTS
DATA
MONI-
TORDATA
MONI-
TOR
(SPEC)ACTIVE
TESTDTC & SRT
CONFIRMATION
DTC*1FREEZE
FRAME
DATA*2SRT
STATUSDTC
WORK
SUP-
PORT
ENGINE CONTROL COMPONENT PARTS
INPUT
Crankshaft position sensor (POS)××××
Camshaft position sensor (PHASE)××××
Mass air flow sensor×××
Engine coolant temperature sensor×××××
Air fuel ratio (A/F) sensor 1×××××
Heated oxygen sensor 2×××××
Wheel sensor××××
Accelerator pedal position sensor×××
Throttle position sensor××××
Fuel tank temperature sensor××××
EVAP control system pressure
sensor×××
Intake air temperature sensor××××
Knock sensor×
Refrigerant pressure sensor××
Closed throttle position switch
(accelerator pedal position sensor
signal)××
Air conditioner switch××
Park/neutral position (PNP) switch×××
St o p l a m p s w it c h×××
Power steering pressure sensor×××
Battery voltage××
Load signal××
Fuel level sensor×××
ICC steering switch×××
ASCD steering switch×××
ICC brake switch×××
ASCD brake switch×××
DTC P1217 ENGINE OVER TEMPERATURE
EC-441
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On Board Diagnosis LogicUBS00H8V
If the cooling fan or another component in the cooling system malfunctions, engine coolant temperature will
rise.
When the engine coolant temperature reaches an abnormally high temperature condition, a malfunction is
indicated.
This self-diagnosis has the one trip detection logic.
CAUTION:
When a malfunction is indicated, be sure to replace the coolant. Refer to CO-10, "
Changing Engine
Coolant" . Also, replace the engine oil. Refer to LU-8, "Changing Engine Oil" .
1. Fill radiator with coolant up to specified level with a filling speed of 2 liters per minute. Be sure to
use coolant with the proper mixture ratio. Refer to MA-12, "
ANTI-FREEZE COOLANT MIXTURE
RATIO" .
2. After refilling coolant, run engine to ensure that no water-flow noise is emitted.
Overall Function CheckUBS00H8W
Use this procedure to check the overall function of the cooling fan. During this check, a DTC might not be con-
firmed.
WA RN ING:
Never remove the radiator cap when the engine is hot. Serious burns could be caused by high pres-
sure fluid escaping from the radiator.
Wrap a thick cloth around cap. Carefully remove the cap by turning it a quarter turn to allow built-up
pressure to escape. Then turn the cap all the way off.
WITH CONSULT-II
1. Check the coolant level in the reservoir tank and radiator.
Allow engine to cool before checking coolant level.
If the coolant level in the reservoir tank and/or radiator is below
the proper range, skip the following steps and go to EC-445,
"Diagnostic Procedure" .
2. Confirm whether customer filled the coolant or not. If customer
filled the coolant, skip the following steps and go to EC-445,
"Diagnostic Procedure" .
3. Turn ignition switch ON.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1217
1217Engine over tempera-
ture (Overheat)
Cooling fan does not operate properly (Over-
heat).
Cooling fan system does not operate prop-
erly (Overheat).
Engine coolant was not added to the system
using the proper filling method.
Engine coolant is not within the specified
range.
Harness or connectors
(The cooling fan circuit is open or
shorted.)
Cooling fan
IPDM E/R (Cooling fan relay)
Radiator hose
Radiator
Radiator cap
Water pump
Thermostat
For more information, refer to EC-448,
"Main 12 Causes of Overheating" .
SEF 6 21 W
EC-442Revision: October 2005
DTC P1217 ENGINE OVER TEMPERATURE
2005 QX56
4. Perform “COOLING FAN” in “ACTIVE TEST” mode with CON-
SULT-II.
5. If the results are NG, go to EC-445, "
Diagnostic Procedure" .
WITH GST
1. Check the coolant level in the reservoir tank and radiator.
Allow engine to cool before checking coolant level.
If the coolant level in the reservoir tank and/or radiator is below
the proper range, skip the following steps and go to EC-445,
"Diagnostic Procedure" .
2. Confirm whether customer filled the coolant or not. If customer
filled the coolant, skip the following steps and go to EC-445,
"Diagnostic Procedure" .
3. Disconnect engine coolant temperature sensor harness connec-
tor.
4. Connect 150Ω resistor to engine coolant temperature sensor
harness connector.
5. Start engine and make sure that cooling fan operates.
CAUTION:
Be careful not to overheat engine.
6. If NG, go to EC-445, "
Diagnostic Procedure" .
SEF 6 46 X
SEF 6 21 W
SEF 8 82 V
EC-448Revision: October 2005
DTC P1217 ENGINE OVER TEMPERATURE
2005 QX56
5. CHECK INTERMITTENT INCIDENT
Perform EC-156, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
OK or NG
OK >> Replace IPDM E/R. Refer to PG-17, "IPDM E/R (INTELLIGENT POWER DISTRIBUTION MOD-
ULE ENGINE ROOM)" .
NG >> Repair or replace harness connectors.
Main 12 Causes of OverheatingUBS00H8Z
*1: Turn the ignition switch ON.
*2: Engine running at 3,000 rpm for 10 minutes.
*3: Drive at 90 km/h (55 MPH) for 30 minutes and then let idle for 10 minutes.
*4: After 60 minutes of cool down time.
For more information, refer to CO-6, "
OVERHEATING CAUSE ANALYSIS" . Engine Step Inspection item Equipment Standard Reference page
OFF 1
Blocked radiator
Blocked condenser
Blocked radiator grille
Blocked bumper
Visual No blocking —
2
Coolant mixtureCoolant tester 50 - 50% coolant mixtureMA-11, "RECOM-
MENDED FLUIDS AND
LUBRICANTS"
3Coolant levelVisual Coolant up to MAX level
in reservoir tank and radi-
ator filler neckCO-10, "Changing
Engine Coolant"
4Radiator capPressure tester 59 - 98 kPa
(0.6 - 1.0 kg/cm2 , 9 - 14
psi) (Limit)CO-10, "
CHECKING
RESERVOIR CAP"
ON*25Coolant leaksVisual No leaksCO-10, "CHECKING
COOLING SYSTEM FOR
LEAKS"
ON*26ThermostatTouch the upper and
lower radiator hosesBoth hoses should be hotCO-19, "THERMOSTAT
AND WATER PIPING"
ON*17Cooling fanCONSULT-II Operating See trouble diagnosis for
DTC P1217 (EC-440,
"DTC P1217 ENGINE
OVER TEMPERATURE"
).
OFF 8
Combustion gas leakColor checker chemical
tester 4 Gas analyzerNegative —
ON*
39Coolant temperature
gaugeVisual Gauge less than 3/4
when driving—
Coolant overflow to
reservoir tankVisual No overflow during driving
and idlingCO-10, "Changing
Engine Coolant"
OFF*410Coolant return from
reservoir tank to radia-
torVisual Should be initial level in
reservoir tankCO-10, "Changing
Engine Coolant"
OFF 11Cylinder headStraight gauge feeler
gauge0.1 mm (0.004 in) Maxi-
mum distortion (warping)EM-63, "Inspection After
Disassembly"
12Cylinder block and pis-
tonsVisual No scuffing on cylinder
walls or pistonEM-89, "Inspection After
Disassembly"
EM-70Revision: October 2005
ENGINE ASSEMBLY
2005 QX56
5. Remove the cowl extension. Refer to EI-18, "Removal and Installation" .
6. Remove the engine room cover using power tools.
7. Remove the air duct and air cleaner case assembly EM-14, "
REMOVAL" .
8. Disconnect the vacuum hose between the vehicle and engine and set it aside.
9. Remove the radiator assembly and hoses. Refer to CO-12, "
REMOVAL" .
10. Remove the drive belts. Refer to EM-12, "
Removal" .
11. Remove the fan blade. Refer to CO-15, "
REMOVAL" .
12. Disconnect the engine room harness from the fuse box and set it aside.
13. Disconnect the ECM.
14. Disconnect the engine room harness from the engine side and set it aside.
15. Disconnect the engine harness grounds.
16. Disconnect the power steering reservoir tank from the engine and move it aside.
17. Disconnect the power steering oil pump from the engine. Move it aside and secure it using suitable wire or
rope. Refer to PS-26, "
REMOVAL" .
18. Remove the A/C compressor bolts and set the compressor aside. Refer to ATC-179, "
REMOVAL" .
19. Disconnect the brake booster vacuum line.
20. Disconnect the EVAP line.
21. Disconnect the fuel hose at the engine side connection. Refer to EM-29, "
REMOVAL" .
22. Disconnect the heater hoses at cowl, and install plugs to avoid leakage of engine coolant.
23. Remove the A/T oil level indicator and indicator tube upper bolts.
24. Remove the front final drive assembly (4x4 only). Refer to FFD-11, "
REMOVAL" .
25. Remove the exhaust manifolds. Refer to EM-19, "
Removal and Installation" .
26. Install the engine slingers into the left bank cylinder head and
right bank cylinder head.
27. Remove the A/T. Refer to AT-244, "
Removal and Installation
(4x2)" or AT-247, "Removal and Installation (4x4)" .
28. Lift using hoist and secure the engine in position.
29. Remove the engine assembly from the vehicle, avoid interfer-
ence with the vehicle body.
CAUTION:
Before and during lifting, always check if any harnesses
are left connected.
30. Remove the parts that may restrict installation of the engine to the engine stand.
NOTE:
This procedure is described assuming that you use an engine stand mounting to the surface to which the
transmission mounts.
a. Remove the drive plate.
Holding the crankshaft pulley bolt, lock the crankshaft to remove the drive plate bolts.
Loosen the bolts diagonally.
WBIA0464E
Engine slinger torque: 45.0 N·m (4.6 kg-m, 33 ft-lb)
PBIC1556E
EM-72Revision: October 2005
ENGINE ASSEMBLY
2005 QX56
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
When replacing an engine or transmission you must make sure the dowels are installed correctly
during re-assembly.
Improper alignment caused by missing dowels may cause vibration, oil leaks or breakage of driv-
etrain components.
INSPECTION AFTER INSTALLATION
Before starting the engine, check oil/fluid levels including engine coolant and engine oil. If the levels are
lower than required quantity, fill to the specified level. Refer to MA-11, "
RECOMMENDED FLUIDS AND
LUBRICANTS" .
Use procedure below to check for fuel leakage.
Turn ignition switch ON (with engine stopped). With fuel pressure applied to the fuel piping, check for fuel
leakage at the connection points.
Start engine. With engine speed increased, check again for fuel leakage at connection points.
Run engine to check for unusual noise and vibration.
Warm up engine thoroughly to make sure there is no leakage of fuel, exhaust gas, or any oils/fluids includ-
ing engine oil and engine coolant.
Bleed air from passages in lines and hoses, such as in cooling system.
After cooling down the engine, again check oil/fluid levels including engine oil and engine coolant. Refill to
specified level if necessary.
Summary of the inspection items:
*Transmission/transaxle/CVT fluid, power steering fluid, brake fluid, etc.Item Before starting engine Engine running After engine stopped
Engine coolant Level Leakage Level
Engine oil Level Leakage Level
Other oils and fluids* Level Leakage Level
Fuel Leakage Leakage Leakage
Exhaust gas — Leakage —
FSU-2
PRECAUTIONS
Revision: October 20052005 QX56
PRECAUTIONSPFP:00001
PrecautionsEES001GD
When installing the rubber bushings, the final tightening must be done under unladen condition and with
the tires on level ground. Oil will shorten the life of the rubber bushings, so wipe off any spilled oil immedi-
ately.
Unladen condition means the fuel tank, engine coolant and lubricants are at the full specification. The
spare tire, jack, hand tools, and mats are in their designated positions.
After installing suspension components, check the wheel alignment.
Lock nuts are not reusable. Always use new lock nuts for installation. New lock nuts are pre-oiled, do not
apply any additional lubrication.