2001 INFINITI QX4 IDX

SEF029Z
DescriptionNBEC0636The refrigerant pressure sensor is installed at the liquid tank of the
air conditioner system. The sensor uses an electrostatic volume
pressure transducer to convert refrigerant pressure to voltage. The
voltage signal is sent to ECM, and ECM controls cooling fan sys-
tem.
SEF099XA
ECM Terminals and Reference ValueNBEC0689Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
58 B/P Sensors' ground[Engine is running]
IWarm-up condition
IIdle speedApproximately 0V
81 W/PURefrigerant pressure
sensor[Engine is running]
IWarm-up condition
IBoth A/C switch and blower switch are ªONº.
(Compressor operates.)1.0 - 4.0V
111 P/B Sensors' power supply[Ignition switch ªONº]Approximately 5V
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REFRIGERANT PRESSURE SENSOR
Description
EC-639

Diagnostic ProcedureNBEC0638
1 CHECK REFRIGERANT PRESSURE SENSOR OVERALL FUNCTION
1. Start engine and warm it up to normal operating temperature.
2. Turn A/C switch and blower switch ªONº.
3. Check voltage between ECM terminal 81 and ground with CONSULT-II or tester.
SEF617XA
OK or NG
OK©INSPECTION END
NG©GO TO 2.
2 CHECK REFRIGERANT PRESSURE SENSOR POWER SUPPLY CIRCUIT
1. Turn A/C switch and blower switch ªOFFº.
2. Stop engine.
3. Disconnect refrigerant pressure sensor harness connector.
SEF029Z
4. Turn ignition switch ªONº.
5. Check voltage between refrigerant pressure sensor terminal 1 and ground with CONSULT-II or tester.
SEF030Z
OK or NG
OK©GO TO 4.
NG©GO TO 3.
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REFRIGERANT PRESSURE SENSOR
Diagnostic Procedure
EC-641

ECM Terminals and Reference ValueNBEC0690Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
52 PU Electrical load signal[Engine is running]
IRear window defogger: ON
IHi-beam headlamp: ONBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
IElectrical load: OFF0V
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ELECTRICAL LOAD SIGNAL
ECM Terminals and Reference Value
EC-643

Diagnostic ProcedureNBEC0605
1 CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-I
1. Turn ignition switch ªONº.
2. Check voltage between ECM terminal 52 and ground under the following conditions.
SEF610X
OK or NG
OK©GO TO 2.
NG©GO TO 3.
2 CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-II
Check voltage between ECM terminal 52 and ground under the following conditions.
SEF611X
OK or NG
OK©INSPECTION END
NG©GO TO 7.
3 CHECK REAR WINDOW DEFOGGER FUNCTION
1. Start engine.
2. Turn ªONº the rear window defogger switch.
3. Check the rear windshield. Is the rear windshield heated up?
YesorNo
Ye s©GO TO 4.
No©Refer to EL-151, ªRear Window Defoggerº.
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ELECTRICAL LOAD SIGNAL
Diagnostic Procedure
EC-645

8 CHECK HEADLAMP INPUT SIGNAL CIRCUIT FOR OPEN OR SHORT
1. Stop engine.
2. Disconnect ECM harness connector.
3. Disconnect headlamp LH relay.
4. Check harness continuity between ECM terminal 52 and headlamp LH relay terminal 7 under the following conditions.
SEF031Z
5. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 10.
NG©GO TO 9.
9 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors E1, M1
IHarness connectors M33, F22
IDiode E121
IHarness for open and short between ECM and headlamp LH relay or daytime light control unit
©Repair open circuit or short to ground or short to power in harness or connectors.
10 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-140.
©INSPECTION END
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ELECTRICAL LOAD SIGNAL
Diagnostic Procedure (Cont'd)
EC-647

Fuel Pressure RegulatorNBEC0408
Fuel pressure at idling kPa (kg/cm2, psi)
Vacuum hose is connected. Approximately 235 (2.4, 34)
Vacuum hose is disconnected. Approximately 294 (3.0, 43)
Idle Speed and Ignition TimingNBEC0409
Target idle speed*1 No-load*2 (in ªPº or Nº position) 750±50 rpm
Air conditioner: ON In ªPº or Nº position 825 rpm or more
Ignition timing*1 In ªPº or Nº position 15ɱ5É BTDC
Throttle position sensor idle position0.15 - 0.85V
*1: Throttle position sensor harness connector connected
*2: Under the following conditions:
IAir conditioner switch: OFF
IElectric load: OFF (Lights, heater fan & rear window defogger)
ISteering wheel: Kept in straight-ahead position
Mass Air Flow SensorNBEC0411
Supply voltageBattery voltage (11 - 14)V
Output voltage at idle1.2 - 1.8*V
Mass air flow (Using CONSULT-II or GST)2.0 - 6.0 g´m/sec at idle*
7.0 - 20.0 g´m/sec at 2,500 rpm*
*: Engine is warmed up to normal operating temperature and running under no-load.
Engine Coolant Temperature SensorNBEC0412
Temperature ÉC (ÉF) Resistance kW
20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.00
90 (194) 0.236 - 0.260
Heated Oxygen Sensor 1 Heater (Front)NBEC0414
Resistance [at 25ÉC (77ÉF)]2.3 - 4.3W
Fuel PumpNBEC0415
Resistance [at 25ÉC (77ÉF)]0.2 - 5.0W
IACV-AAC ValveNBEC0416
Resistance [at 20ÉC (68ÉF)]Approximately 20 - 24W
InjectorNBEC0417
Resistance [at 20ÉC (68ÉF)]13.5 - 17.5W
ResistorNBEC0418
Resistance [at 25ÉC (77ÉF)]Approximately 2.2 kW
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SERVICE DATA AND SPECIFICATIONS (SDS)
Fuel Pressure Regulator
EC-649

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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Schematic ................................................................255
Wiring Diagram - D/LOCK -.....................................256
Trouble Diagnoses...................................................261
MULTI-REMOTE CONTROL SYSTEM.......................270
Component Parts and Harness Connector
Location ...................................................................270
System Description ..................................................270
Schematic ................................................................273
Wiring Diagram - MULTI - .......................................274
Trouble Diagnoses...................................................277
ID Code Entry Procedure ........................................289
Remote Controller Battery Replacement.................293
THEFT WARNING SYSTEM.......................................294
Component Parts and Harness Connector
Location ...................................................................294
System Description ..................................................295
Schematic ................................................................298
Wiring Diagram - THEFT -.......................................300
Trouble Diagnoses...................................................306
SMART ENTRANCE CONTROL UNIT.......................319
Description ...............................................................319
Schematic ................................................................322
Smart Entrance Control Unit Inspection Table ........324
INTEGRATED HOMELINK TRANSMITTER...............325
Wiring Diagram - TRNSMT - ...................................325
Trouble Diagnoses...................................................326
IVIS (INFINITI VEHICLE IMMOBILIZER SYSTEM -
NATS)...........................................................................328
Component Parts and Harness Connetor
Location ...................................................................328
System Description ..................................................329
System Composition ................................................329
Wiring Diagram - NATS -.........................................330
CONSULT-II .............................................................331
Trouble Diagnoses...................................................334
How to Replace IVIS (NATS) IMMU .......................347
INFINITI COMMUNICATOR (IVCS)............................348
Precaution ................................................................348
Communicator Response Center Telephone
Number for Technicians ...........................................348
Component Parts and Harness Connector
Location ...................................................................349System Description ..................................................350
Schematic ................................................................358
Wiring Diagram - IVCS -..........................................359
CONSULT-II .............................................................363
Trouble Diagnoses...................................................368
Trouble Diagnoses for Intermittent Incident ............377
Demonstration Mode ...............................................379
System Setting (When IVCS Unit is Replaced) ......381
NAVIGATION SYSTEM...............................................385
Component Parts Location ......................................385
System Description ..................................................386
Schematic ................................................................393
Wiring Diagram - NAVI - ..........................................394
Self-diagnosis Mode ................................................397
Confirmation/Adjustment Mode ...............................400
Setting Mode............................................................410
Trouble diagnoses ...................................................417
This Condition is Not Abnormal ...............................423
Program Loading .....................................................432
Initialization ..............................................................433
ELECTRICAL UNITS LOCATION...............................436
Engine Compartment ...............................................436
Passenger Compartment .........................................438
HARNESS LAYOUT....................................................440
How to Read Harness Layout .................................440
Outline......................................................................441
Main Harness...........................................................442
Engine Room Harness ............................................444
Engine Control Harness ..........................................446
Body Harness LH ....................................................448
Body Harness RH ....................................................449
Back Door Harness .................................................450
Engine and Transmission Harness..........................451
Room Lamp Harness...............................................452
Air Bag Harness ......................................................453
Front Door Harness .................................................454
Rear Door Harness..................................................455
BULB SPECIFICATIONS............................................456
Headlamp.................................................................456
Exterior Lamp ..........................................................456
Interior Lamp............................................................456
WIRING DIAGRAM CODES (CELL CODES).............457GI
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CONTENTS(Cont'd)
EL-3