2001 INFINITI QX4 tensioner

ELECTRICAL SYSTEM
SECTION
EL
CONTENTS
PRECAUTIONS...............................................................4
Supplemental Restraint System (SRS)²AIR
BAG²and²SEAT BELT PRE-TENSIONER²...............4
Wiring Diagrams and Trouble Diagnosis .....................4
HARNESS CONNECTOR................................................5
Description ...................................................................5
STANDARDIZED RELAY................................................7
Description ...................................................................7
POWER SUPPLY ROUTING...........................................9
Schematic ....................................................................9
Wiring Diagram - POWER - ......................................10
Inspection...................................................................16
GROUND........................................................................17
Ground Distribution ....................................................17
COMBINATION SWITCH..............................................28
Check .........................................................................28
Replacement ..............................................................29
STEERING SWITCH......................................................30
Check .........................................................................30
HEADLAMP (FOR USA) - XENON TYPE -..................31
Component Parts and Harness Connector
Location .....................................................................31
System Description ....................................................31
Schematic ..................................................................35
Wiring Diagram - H/LAMP -.......................................36
Trouble Diagnoses.....................................................40
Bulb Replacement/Xenon Type .................................43
Aiming Adjustment .....................................................44
HEADLAMP (FOR CANADA) - DAYTIME LIGHT
SYSTEM -......................................................................46
Component Parts and Harness Connector
Location .....................................................................46
System Description ....................................................46
Schematic ..................................................................50
Wiring Diagram - DTRL - ...........................................51
Trouble Diagnoses.....................................................56
Bulb Replacement .....................................................57
Aiming Adjustment .....................................................58
HEADLAMP - HEADLAMP AIMING CONTROL -........59System Description ....................................................59
Wiring Diagram - H/AIM - ..........................................60
PARKING, LICENSE AND TAIL LAMPS.....................61
System Description ....................................................61
Schematic ..................................................................62
Wiring Diagram - TAIL/L - ..........................................63
Trouble Diagnoses.....................................................66
STOP LAMP..................................................................67
Wiring Diagram - STOP/L - .......................................67
BACK-UP LAMP............................................................69
Wiring Diagram - BACK/L - .......................................69
FRONT FOG LAMP.......................................................70
System Description ....................................................70
Wiring Diagram - F/FOG - .........................................72
Aiming Adjustment .....................................................74
TURN SIGNAL AND HAZARD WARNING LAMPS.....75
System Description ....................................................75
Wiring Diagram - TURN - ..........................................77
Trouble Diagnoses.....................................................79
Electrical Components Inspection .............................79
ILLUMINATION..............................................................80
System Description ....................................................80
Schematic ..................................................................82
Wiring Diagram - ILL - ...............................................83
INTERIOR, SPOT, VANITY MIRROR AND
LUGGAGE ROOM LAMPS...........................................88
System Description ....................................................88
Schematic ..................................................................90
Wiring Diagram - INT/L - ...........................................91
METERS AND GAUGES...............................................94
Component Parts and Harness Connector
Location .....................................................................94
System Description ....................................................94
Combination Meter ....................................................96
Schematic ..................................................................98
Wiring Diagram - METER - .......................................99
Meter/Gauge Operation and Odo/Trip Meter
Segment Check in Diagnosis Mode ........................100
Trouble Diagnoses...................................................101
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Supplemental Restraint System (SRS) ªAIR
BAGº and ªSEAT BELT PRE-TENSIONERº
NBEL0001The Supplemental Restraint System such as ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº used along with
a seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain types of
collision. The SRS system composition which is available to INFINITI QX4 is as follows:
IFor a frontal collision
The Supplemental Restraint System consists of driver air bag module (located in the center of the steer-
ing wheel), front passenger air bag module (located on the instrument panel on passenger side), seat belt
pre-tensioners, a diagnosis sensor unit, warning lamp, wiring harness and spiral cable.
IFor a side collision
The Supplemental Restraint System consists of side air bag module (located in the outer side of front seat),
satellite sensor, diagnosis sensor unit (one of components of air bags for a frontal collision), wiring harness,
warning lamp (one of components of air bags for a frontal collision).
Information necessary to service the system safely is included in theRS sectionof this Service Manual.
WARNING:
ITo avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be performed
by an authorized INFINITI dealer.
IImproper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the RS section.
IDo not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. Spiral cable and wiring harnesses covered with yellow insulation tape either just
before the harness connectors or for the complete harness are related to the SRS.
Wiring Diagrams and Trouble DiagnosisNBEL0002When you read wiring diagrams, refer to the following:
IGI-11, ªHOW TO READ WIRING DIAGRAMSº
IEL-9, ªPOWER SUPPLY ROUTINGº for power distribution circuit
When you perform trouble diagnosis, refer to the following:
IGI-35, ªHOW TO FOLLOW TEST GROUPS IN TROUBLE DIAGNOSESº
IGI-24, ªHOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENTº
Check for any Service bulletins before servicing the vehicle.
PRECAUTIONS
Supplemental Restraint System (SRS) ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº
EL-4

NVH Troubleshooting Ð Engine NoiseNBEM0005S01Use the chart below to help you find the cause of the symptom.
1. Locate the area where noise occurs.
2. Confirm the type of noise.
3. Specify the operating condition of engine.
4. Check specified noise source.
If necessary, repair or replace these parts.
Location of
noiseType of
noiseOperating condition of engine
Source of
noiseCheck itemReference
page Before
warm-upAfter
warm-upWhen
startingWhen
idlingWhen
racingWhile
driving
To p o f
engine
Rocker
cover
Cylinder
headTicking or
clickingC A ÐA BÐTappet
noiseValve clearance EM-54
Rattle C A Ð A B CCamshaft
bearing
noiseCamshaft journal clear-
ance
Camshaft runoutEM-42, 42
Crankshaft
pulley
Cylinder
block
(Side of
engine)
Oil panSlap or
knockÐ A ÐB BÐPiston pin
noisePiston and piston pin
clearance
Connecting rod bush-
ing clearanceEM-63, 70
Slap or
rapA ÐÐBBAPiston slap
noisePiston-to-bore clear-
ance
Piston ring side clear-
ance
Piston ring end gap
Connecting rod bend
and torsionEM-64, 64,
65, 66
Knock A B C B B BConnect-
ing rod
bearing
noiseConnecting rod bush-
ing clearance (Small
end)
Connecting rod bearing
clearance (Big end)EM-70, 69
Knock A B Ð A B CMain bear-
ing noiseMain bearing oil clear-
ance
Crankshaft runoutEM-67, 67
Front of
engine
Timing
chain
coverTapping or
tickingA A ÐBBBTiming
chain and
chain ten-
sioner
noiseTiming chain cracks
and wear
Timing chain tensioner
operationEM-29, 20
Front of
engineSqueaking
or fizzingA B ÐBÐCOther
drive belts
(Sticking
or slipping)Drive belts deflectionMA section
(ªChecking
Drive
Beltsº,
ªENGINE
MAINTE-
NANCEº) Creaking A BABABOther
drive belts
(Slipping)Idler pulley bearing
operation
Squall
CreakA B ÐBABWater
pump
noiseWater pump operationLC section
(ªWater
Pump
Inspectionº,
ªENGINE
COOLING
SYSTEMº)
A: Closely related B: Related C: Sometimes related Ð: Not related
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NOISE, VIBRATION AND HARSHNESS (NVH) TROUBLESHOOTING
NVH Troubleshooting Ð Engine Noise
EM-9

ComponentsNBEM0011
JEM410G
1. Rear timing chain case
2. Left camshaft chain tensioner
3. Internal guide
4. Timing chain (Secondary)
5. Right camshaft chain tensioner
6. Timing chain tensioner
7. Slack guide
8. Timing chain (Primary)9. Crankshaft sprocket
10. Lower tension guide
11. Upper tension guide
12. Front timing chain case
13. Crankshaft pulley
14. Water pump cover
15. Chain tensioner cover
16. Exhaust camshaft sprocket17. CVTC cover
18. Intake camshaft sprocket
19. PHASE sensor
20. CVTC sensor
21. Variable induction air control valve
control solenoid valve
22. Swirl control valve control solenoid
valve
TIMING CHAIN
Components
EM-20

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

SEM919EA
30. Remove internal chain guide.
31. Remove upper tension guide.
32. Remove timing chain tensioner and slack guide.
SEM966F
IRemove timing chain tensioner. (Push piston and insert a suit-
able pin into pinhole.)
SEM425G
33. Attach a suitable stopper pin to RH and LH camshaft chain
tensioners.
SEM426G
34. Remove intake and exhaust camshaft sprocket bolts.
IApply paint to timing chain and camshaft sprockets for
alignment during installation.
ISecure the hexagonal head of the camshaft using a span-
ner to loosen mounting bolts.
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TIMING CHAIN
Removal (Cont'd)
EM-27

SEM928E
InspectionNBEM0013Check for cracks and excessive wear at roller links. Replace
chain if necessary.
SEM930E
InstallationNBEM00141. Position crankshaft so that No. 1 piston is set at TDC on com-
pression stroke.
SEM929E
2. Install crankshaft sprocket on crankshaft.
IMake sure that mating marks on crankshaft sprocket face
front of engine.
SEM931E
3. Install lower chain guide on dowel pin, with front mark on the
guide facing upside.
SEM430G
4. Press and shrink the secondary chain tensioner sleeve, and fix
it using stopper pins.
ILubricate threads and seat surfaces of camshaft sprocket bolts
with new engine oil.
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TIMING CHAIN
Inspection
EM-29

SEM426G
7. After confirming the mating marks are aligned, tighten the cam-
shaft sprocket mounting bolts.
ISecure the camshaft hexagonal head using a spanner to
tighten mounting bolts.
SEM425G
8. Pull out the stopper pin from the secondary timing chain ten-
sioner.
SEM919EA
9. Install internal guide.
10. Install upper tension guide and slack guide.
SEM967F
11. Install timing chain tensioner, then remove the stopper pin.
IWhen installing the timing chain tensioner, engine oil
should be applied to the oil hole and tensioner.
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TIMING CHAIN
Installation (Cont'd)
EM-31