2001 INFINITI QX4 relay

4 CHECK REAR WINDOW DEFOGGER INPUT SIGNAL CIRCUIT FOR OPEN OR SHORT
1. Stop engine.
2. Disconnect ECM harness connector.
3. Disconnect rear window defogger relay.
4. Check harness continuity between ECM terminal 52 and rear window defogger relay terminals 7.
SEF031Z
5. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 6.
NG©GO TO 5.
5 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors E1, M1
IHarness connectors M33, F22
IDiode M37
IHarness for open and short between ECM and rear window defigger relay
©Repair open circuit or short to ground or short to power in harness or connectors.
6 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-140.
©INSPECTION END
7 CHECK HEADLAMP FUNCTION
1. Start engine.
2. Turn the lighting switch ªONº at 1st position with high beam.
3. Check that headlamps are illuminated.
OK or NG
OK©GO TO 8.
NG©Refer to EL-60, ªHEADLAMP (FOR USA)º or EL-123, ªHEADLAMP (FOR CANADA) Ð
DAYTIME LIGHT SYSTEMº.
ELECTRICAL LOAD SIGNAL
Diagnostic Procedure (Cont'd)
EC-646

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

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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DescriptionNBEL0004NORMAL OPEN, NORMAL CLOSED AND MIXED TYPE RELAYSNBEL0004S01Relays can mainly be divided into three types: normal open, normal closed and mixed type relays.
SEL881H
TYPE OF STANDARDIZED RELAYSNBEL0004S02
1M 1 Make 2M 2 Make
1T 1 Transfer 1M´1B 1 Make 1 Break
SEL882H
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STANDARDIZED RELAY
Description
EL-7

GEL264
STANDARDIZED RELAY
Description (Cont'd)
EL-8

Component Parts and Harness Connector
Location
NBEL0159
SEL460X
System DescriptionNBEL0188The headlamp operation is controlled by the lighting switch which is built into the combination switch and
headlamp battery saver control unit. And the headlamp battery saver system is controlled by the headlamp
battery saver control unit and smart entrance control unit.
OUTLINENBEL0188S01Power is supplied at all times
Ito headlamp LH relay terminals 1 and 3
Ithrough 15A fuse (No. 60, located in the fuse and fusible link box), and
Ito headlamp LH relay terminal 6
Ithrough 20A fuse (No. 32, located in the fuse and fusible link box), and
Ito headlamp RH relay terminals 1 and 3
Ithrough 15A fuse (No. 59, located in the fuse and fusible link box), and
Ito headlamp RH relay terminal 6
Ithrough 20A fuse (No. 31, located in the fuse and fusible link box), and
Ito headlamp battery saver control unit terminal 7, and
Ito smart entrance control unit terminal 10
Ithrough 7.5A fuse [No. 24, located in the fuse block (J/B)].
When the ignition switch is in the ON or START position, power is supplied
Ito headlamp battery saver control unit terminal 1
Ithrough 10A fuse [No. 16, located in the fuse block (J/B)], and
Ito headlamp battery saver control unit terminal 10,
Ito auto light control unit terminal 1 and
Ito smart entrance control unit terminal 33
Ithrough 7.5A fuse [No. 11, located in the fuse block (J/B)].
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HEADLAMP (FOR USA) Ð XENON TYPE Ð
Component Parts and Harness Connector Location
EL-31

When the ignition switch is in the ACC or ON position, power is supplied
Ito auto light control unit terminal 2
Ithrough 10A fuse [No. 9, located in the fuse block (J/B)]
Ground is supplied
Ito headlamp battery saver control unit terminals 4 and 11
Ithrough body grounds M77 and M111, and M4,M66 and M147
Ito auto light control unit terminal 5
Ithrough body grounds M4, M66 and M147.
Power Supply to Low Beam and High BeamNBEL0188S0101When lighting switch is in 2ND or PASS position, ground is supplied
Ito headlamp relay (LH and RH) terminal 2 from headlamp battery saver control unit terminals 2 and 8
Ithrough headlamp battery saver control unit terminals 3 and 9,
Ifrom lighting switch terminal 12.
Headlamp relays (LH and RH) are energized and then power is supplied to headlamps (LH and RH).
LOW BEAM OPERATIONNBEL0188S02When the lighting switch is turned to the 2ND position and placed in LOW (ªBº) position, power is supplied
Ifrom terminal 7 of each headlamp relay
Ito terminal 3 of each headlamp
Ground is supplied
Ito terminal 4 of each headlamp
Ithrough body grounds E13 and E41.
With power and ground supplied, the headlamp(s) will illuminate.
HIGH BEAM OPERATION/FLASH-TO-PASS OPERATIONNBEL0188S03When the lighting switch is turned to the 2ND position and placed in HIGH (ªAº) position or PASS (ªCº) position,
power is supplied
Ifrom terminal 5 of headlamp LH relay
Ito terminal 1 of headlamp LH, and
Ito combination meter terminal 26 for the HIGH BEAM indicator
Ifrom terminal 5 of headlamp RH relay
Ito terminal 1 of headlamp RH.
Ground is supplied
Ito headlamp LH terminal 2
Ito combination meter terminal 27 for the HIGH BEAM indicator
Ithrough lighting switch terminals 6 and 5
Ithrough body grounds E13 and E41, and
Ito headlamp RH terminal 2
Ithrough lighting switch terminals 9 and 8
Ithrough body grounds E13 and E41.
With power and ground supplied, the high beams and the high beam indicator illuminate.
BATTERY SAVER CONTROLNBEL0188S04When the ignition switch is turned from ON (or START) to OFF (or ACC) positions while headlamps illuminate,
the RAP signal is supplied to terminal 10 of the headlamp battery saver control unit from smart entrance con-
trol unit terminal 5.
After counting 45 seconds by the RAP signal from the smart entrance control unit to headlamp battery saver
control unit, the ground supply to terminal 2 of the headlamp LH and RH relay from headlamp battery saver
control unit terminals 2 and 8 is terminated.
Then the headlamps are turned off.
The headlamps are turned off when driver or passenger side door is opened even if 45 seconds have not
passed after ignition switch is turned from ON (or START) to OFF (or ACC) positions while headlamps are
illuminated.
When the lighting switch is turned from OFF to 2ND after headlamps are turned to off by the battery saver
control, ground is supplied
HEADLAMP (FOR USA) Ð XENON TYPE Ð
System Description (Cont'd)
EL-32

Ito headlamp battery saver control unit terminals 5 and 13 from lighting switch terminal 11, and
Ito headlamp LH and RH relays terminal 2 from headlamp battery saver control unit terminals 2 and 8
Ithrough headlamp battery saver control unit terminals 3 and 9, and
Ithrough lighting switch terminal 12.
Then headlamps illuminate again.
AUTO LIGHT OPERATIONNBEL0188S05When lighting switch is in ªAUTOº position, ground is supplied
Ito auto light control unit terminal 10
Ifrom lighting switch terminal 42.
When ignition switch is turn to ªONº or ªSTARTº position and outside brightness is darker than prescribed level.
Ground is supplied
Ito headlamp relay LH and RH terminals 2
Ithrough battery saver control unit
Ifrom auto light control unit terminal 6, and
Ito tail lamp relay terminal 1
Ithrough battery saver control unit
Ifrom auto light control unit terminal 7.
Then both headlamp relays and tail lamp relay are energized, headlamps (low or high) and tail lamps are illu-
minate according to switch position.
Auto light operation allows headlamps and tail lamps to go off when
IIgnition switch is turned to ªOFFº position or
IOutside brightness is brighter than prescribed level.
NOTE:
The delay time is varies up to maximum of 20 seconds as the outside brightness changes.
For parking, license and tail lamp auto operation, refer to ªPARKING, LICENSE AND TAIL LAMPSº.
THEFT WARNING SYSTEMNBEL0188S06The theft warning system will flash the low beams if the system is triggered. Refer to ªTHEFT WARNING
SYSTEMº (EL-296).
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HEADLAMP (FOR USA) Ð XENON TYPE Ð
System Description (Cont'd)
EL-33