2001 INFINITI QX4 engine coolant

POWER SUPPLY AND GROUND CIRCUITNBEL0042S08Power is supplied at all times
Ithrough 7.5A fuse [No. 24, located in the fuse block (J/B)]
Ito combination meter terminal 62.
With the ignition switch in the ON or START position, power is supplied
Ithrough 10A fuse [No. 8, located in the fuse block (J/B)]
Ito combination meter terminal 66.
Ground is supplied
Ito combination meter terminal 59
Ithrough body grounds M4, M66 and M147.
WATER TEMPERATURE GAUGENBEL0042S01The water temperature gauge indicates the engine coolant temperature. The reading on the gauge is based
on the resistance of the thermal transmitter.
As the temperature of the coolant increases, the resistance of the thermal transmitter decreases. A variable
ground is supplied to terminal 18 of the combination meter for the water temperature gauge. The needle on
the gauge moves from ªCº to ªHº.
TACHOMETERNBEL0042S02The tachometer indicates engine speed in revolutions per minute (rpm).
The tachometer is regulated by a signal
Ifrom terminal 25 of the ECM
Ito combination meter terminal 16 for the tachometer.
FUEL GAUGENBEL0042S03The fuel gauge indicates the approximate fuel level in the fuel tank.
The fuel gauge is regulated by a variable ground signal supplied
Ito combination meter terminal 17 for the fuel gauge
Ifrom terminal 3 of the fuel level sensor unit
Ithrough terminal 2 of the fuel level sensor unit and
Ithrough body grounds B11, B22 and D210.
SPEEDOMETERNBEL0042S04The vehicle speed sensor provides a voltage signal to the combination meter for the speedometer.
The voltage is supplied
Ifrom combination meter terminal 15 for the speedometer
Ito terminal 2 of the vehicle speed sensor.
The speedometer converts the voltage into the vehicle speed displayed.
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METERS AND GAUGES
System Description (Cont'd)
EL-95

NBEL0145
Use the chart below to find out what each wiring
diagram code stands for.
Refer to the wiring diagram code in the alphabetical
index to find the location (page number) of each
wiring diagram.
Code Section Wiring Diagram Name
1STSIG AT A/T 1ST Signal
2NDSIG AT A/T 2ND Signal
3RDSIG AT A/T 3RD Signal
4THSIG AT A/T 4TH Signal
A/C, A HA Auto Air Conditioner
AAC/V EC IACV-AAC Valve
ABS BR Anti-lock Brake System
AP/SEN EC Absolute Pressure Sensor
ASCD EL Automatic Speed Control Device
AT/C EC A/T Control
ATDIAG EC A/T Diagnosis Communication
Line
AT/IND EL A/T Indicator Lamp
AUDIO EL Audio
AUT/DP EL Automatic Drive Positioner
BA/FTS AT A/T Fluid Temperature Sensor
and TCM Power Supply
BACK/L EL Back-up Lamp
BYPS/V EC Vacuum Cut Valve Bypass Valve
CHARGE SC Charging System
CHIME EL Warning Chime
CIGAR EL Cigarette Lighter
CLOCK EL Clock
COMPAS EL Compass and Thermometer
D/LOCK EL Power Door Lock
DEF EL Rear Window Defogger
DTRL EL Headlamp Ð With Daytime Light
System Ð
ECTS EC Engine Coolant Temperature Sen-
sor
ENGSS AT Engine Speed Signal
F/FOG EL Front Fog Lamp
F/LID EL Fuel Lid Opener
F/PUMP EC Fuel Pump Control
FICD EC IACV-FICD Solenoid Valve
FLS1 EC Fuel Gauge
Code Section Wiring Diagram Name
FLS2 EC Fuel Gauge
FLS3 EC Fuel Gauge
FTS AT A/T Fluid Temperature Sensor
FUELLH EC Fuel Injection System Function
(Left Bank)
FUELRH EC Fuel Injection System Function
(Right Bank)
H/AIM EL Headlamp Aiming Control System
H/LAMP EL Headlamp
HORN EL Horn
HSEAT EL Heated Seat
IATS EC Intake Air Temperature Sensor
IGN/SG EC Ignition Signal
ILL EL Illumination
INJECT EC Injector
INT/L EL Interior, Spot, Vanity Mirror, and
Luggage Room Lamps
IVC-L EC Intake Valve Timing Control Sole-
noid Valve LH
IVC-R EC Intake Valve Timing Control Sole-
noid Valve RH
IVCS EL INFINITI Communicator
IVCS-L EC Intake Valve Timing Control Posi-
tion Sensor LH
IVCS-R EC Intake Valve Timing Control Posi-
tion Sensor RH
KS EC Knock Sensor
LAN AT A/T Communication Line
LOAD EC Electrical Load Signal
LPSV AT Line Pressure Solenoid Valve
MAFS EC Mass Air Flow Sensor
MAIN AT Main Power Supply and Ground
Circuit
MAIN EC Main Power Supply and Ground
Circuit
METER EL Speedometer, Tachometer, Temp.,
Oil, and Fuel Gauges
MIL/DL EC MIL and Data Link Connectors
MIRROR EL Door Mirror
MULTI EL Multi-remote Control System
NATS EL IVIS (Infiniti Vehicle Immobiliser
System)
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WIRING DIAGRAM CODES (CELL CODES)
EL-457

Parts Requiring Angular TighteningNBEM0001IUse an angle wrench for the final tightening of the following
engine parts:
a) Cylinder head bolts
b) Main bearing cap bolts
c) Connecting rod cap bolts
d) Crankshaft pulley bolt
IDo not use a torque value for final tightening.
IThe torque value for these parts are for a preliminary step.
IEnsure thread and seat surfaces are clean and coated with
engine oil.
SEM164F
Liquid Gasket Application ProcedureNBEM00021.Use a scraper to remove all traces of old liquid gasket
from mating surfaces and grooves. Also, completely clean
any oil from these areas.
2.Apply a continuous bead of liquid gasket to mating sur-
faces. (Use Genuine RTV silicone sealant Part No. 999MP-
A7007 or equivalent.)
IBe sure liquid gasket diameter is as specified.
AEM080
3.Apply liquid gasket around the inner side of bolt holes
(unless otherwise specified).
4.Assembly should be done within 5 minutes after coating.
5.Wait at least 30 minutes before refilling engine oil and
engine coolant.
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PRECAUTIONS
Parts Requiring Angular Tightening
EM-3

SEM484GA
1. Heated oxygen sensor 1 (front)
(bank 1)
2. Heated oxygen sensor 1 (front)
(bank 2)
3. TWC (manifold)4. Thermostat with water inlet
5. Exhaust manifold
6. Thermal transmitter
7. Engine coolant temperature8. Water control valve
9. Water outlet housing
10. Cylinder block water outlet
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OUTER COMPONENT PARTS
Removal and Installation (Cont'd)
EM-11

ComponentsNBEM0008
SEM583G
RemovalNBEM0009WARNING:
IPlace vehicle on a flat and solid surface.
IYou should not remove oil pan until exhaust system and
cooling system have completely cooled off.
Otherwise, you may burn yourself and/or fire may break
out in the fuel line.
IWhen removing front engine mounting nuts, lift up slightly
engine for safety work.
CAUTION:
When removing the aluminum oil pan from engine, first
remove the crankshaft position sensors (POS and REF) from
the assembly.
Be careful not to damage sensor edges and signal plate teeth.
1. Remove front RH and LH wheels.
2. Remove battery.
3. Remove oil level gauge.
4. Remove engine undercover.
5. Remove suspension member stay.
6. Drain engine coolant from radiator drain plug.
7. Disconnect A/T oil cooler hoses.
8. Drain engine oil.
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OIL PAN
Components
EM-15

CAUTION:
IAfter removing timing chain, do not turn crankshaft and
camshaft separately, or valves will strike piston heads.
IWhen installing camshafts, chain tensioners, oil seals, or
other sliding parts, lubricate contacting surfaces with new
engine oil.
IApply new engine oil to bolt threads and seat surfaces
when installing camshaft sprockets and crankshaft pulley.
IBefore disconnecting fuel hose, release fuel pressure.
Refer to EC-39, ªFuel Pressure Releaseº.
IBe careful not to damage sensor edges.
IDo not spill engine coolant on drive belts.
RemovalNBEM00121. Release fuel pressure.
Refer to EC-39, ªFuel Pressure Releaseº.
2. Remove battery.
3. Remove radiator.
Refer to LC-19, ªREMOVAL AND INSTALLATIONº.
4. Drain engine oil.
5. Remove drive belts and idler pulley with brackets.
6. Remove cooling fan with bracket.
7. Remove engine cover.
8. Remove air duct with air cleaner case, collector, blow-by hose,
vacuum hoses, fuel hoses, water hoses, wires, harnesses,
connectors and so on.
9. Remove the air compressor, and tie it down using rope or the
like to keep it from interfering.
10. Remove the power steering oil pump and reservoir tank. Tie
them down using rope or the like to keep them from interfer-
ing.
11. Remove alternator.
12. Remove the following.
IVacuum gallery
IWater bypass pipe
IBrackets
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TIMING CHAIN
Components (Cont'd)
EM-23

Rear Engine MountingNBEM0042S0102
SEM459G
SEM605G
SEM461G
SEM324F
1. Release fuel pressure.
Refer to EC-39, ªFuel pressure releaseº.
2. Remove engine hood and front RH and LH wheels.
3. Remove engine undercover and suspension member stay.
4. Drain coolant from radiator.
5. Remove the following parts.
IRadiator shroud
IRadiator
ICooling fan
IDrive belts
IBattery
IEngine cover
IThrottle wires
6. Air duct with air cleaner case.
7. Disconnect vacuum hoses, fuel hoses, heater hoses, EVAP
canister hoses, harnesses, connectors and so on.
8. Remove air conditioner compressor from bracket, then put it
aside holding with a suitable wire.
9. Remove power steering oil pump and reservoir tank with
bracket, then put it aside holding with a suitable wire.
10. Remove alternator.
11. Remove exhaust front tube heat insulators, then remove rear
heated oxygen sensors.
12. Remove exhaust front and rear tubes.
Refer to FE-8, ªRemoval and Installationº.
13. Remove transmission with transfer.
Refer to AT-277, ªRemovalº.
14. Remove TWC (manifold) heat insulators, then remove TWC
(manifold).
15. Install engine slingers.
16. Hoist engine with engine slingers and remove front engine
mounting nuts.
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ENGINE ASSEMBLY
Removal and Installation (Cont'd)
EM-59

CYLINDER BLOCK HEATERNBEM0024S02
SEM537G
SEM180FA
Removal and InstallationNBEM0025CAUTION:
IWhen installing bearings, pistons, or other sliding parts,
lubricate contacting surfaces with new engine oil.
IPlace removed parts such as bearings and bearing caps
in their proper order and direction.
IWhen installing connecting rod nuts, and main bearing
cap bolts, apply new engine oil to threads and seating
surfaces.
IDo not allow any magnetic materials to contact the signal
plate teeth of drive plate.
SEM190FA
DisassemblyNBEM0026PISTON, CRANKSHAFT AND OIL JETNBEM0026S011. Remove engine. Refer to ªRemoval and Installationº, EM-57.
2. Place engine on a work stand.
3. Drain coolant and oil.
4. Remove oil pan. Refer to ªRemovalº, EM-15.
5. Remove timing chain. Refer to ªRemovalº, EM-23.
6. Remove cylinder head. Refer to ªRemovalº, EM-23.
CYLINDER BLOCK
Components (Cont'd)
EM-62