2004 INFINITI QX56 fuse

TRAILER TOW
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TRAILER TOWPFP:93020
Component Parts and Harness Connector LocationEKS007CT
System DescriptionEKS007CU
Power is supplied at all times

through 50A fusible link (letter f , located in the fuse and fusible link box)

to BCM (body control module) terminal 70, and

through 10A fuse [No. 32, located in the IPDM E/R (intelligent power distribution module engine room)]

through IPDM E/R terminal 61

to trailer tow relay 1 terminal 3, and

through 20A fuse (No. 53, located in the IPDM E/R)

to CPU of the IPDM E/R, and

through 30A fusible link (letter j , located in the fuse and fusible link box)

to trailer tow relay 2 terminals 3 and 6, and

through 40A fusible link (letter k , located in the fuse and fusible link box)

to electric brake (pre-wiring) terminal 5.
With the ignition switch in the ON or START position, power is supplied
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LT-124
TRAILER TOW
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through 10A fuse (No. 59, located in the fuse and relay box)

to BCM terminal 38, and

through 10A fuse (No. 51, located in the IPDM E/R)

to trailer tow relay 2 terminal 1.
Ground is supplied

to BCM terminal 67 and

to electric brake (pre-wiring) terminal 1

through grounds M57, M61 and M79, and

to IPDM E/R terminals 38 and 59

to trailer tow relay 1 terminal 2

to trailer tow relay 2 terminal 2 and

to trailer connector terminal 2

through grounds E9, E15 and E24.
TRAILER TAIL LAMP OPERATION
The trailer tail lamps are controlled by the trailer tow relay 1.
With the lighting switch in the parking and tail lamp ON (1ST) position, AUTO position (and the auto light sys-
tem is activated) or headlamp ON (2ND) position, power is supplied

through the tail lamp relay, located in the IPDM E/R

through 10A fuse (No. 36, located in the IPDM E/R)

through IPDM E/R terminal 49

to trailer tow relay 1 terminal 1.
When energized, trailer tow relay 1 supplies tail lamp power to trailer connector terminal 6.
TRAILER BRAKE, TURN SIGNAL AND HAZARD LAMP OPERATION
The trailer brake, turn signal and hazard lamps are all controlled by the BCM. When the brake pedal is
depressed, the BCM receives stop lamp switch signal through CAN communication. If the brake pedal is
depressed or either turn signal or the hazard lamps are turned on, the BCM supplies voltage to the trailer
lamps to make them flash or turn on.
Left trailer brake, turn signal and hazard lamp output is supplied

through BCM terminal 52

to trailer connector terminal 1.
Right trailer brake, turn signal and hazard lamp output is supplied

through BCM terminal 51

to trailer connector terminal 4.
TRAILER BRAKE OPERATION
The trailer brake is controlled by the electric brake. The electric brake receives stop lamp switch signal at elec-
tric brake (pre-wiring) terminal 2 when the brake pedal is depressed.
When the brake pedal is depressed, power is supplied by the electric brake

through electric brake (pre-wiring) terminal 3

to trailer connector terminal 3.
TRAILER POWER SUPPLY OPERATION
The trailer power supply is controlled by the trailer tow relay 2.
When the ignition switch is in the ON or START position, power is supplied

through 10A fuse (No. 51, located in the IPDM E/R)

to IPDM E/R terminal 16

to trailer tow relay 2 terminal 1.
When energized, the trailer tow relay 2 supplies power

through trailer tow relay 2 terminals 5 and 7

to trailer connector terminal 5.

LT-130
INTERIOR ROOM LAMP
Revision: August 20072004 QX56
System DescriptionEKS007CY
When room lamp and personal lamp switch is in DOOR position, room lamp and personal lamp ON/OFF is
controlled by timer according to signals from switches including key switch and key lock solenoid, front door
switch LH, unlock signal from keyfob, door lock and unlock switch, front door lock assembly LH (key cylinder
switch), ignition switch, and glass hatch ajar switch.
When room lamp and personal lamp turns ON, there is a gradual brightening over 1 second. When room lamp
and personal lamp turns OFF, there is a gradual dimming over 1 second.
The room lamp and personal lamp timer is controlled by the BCM (body control module).
Room lamp and personal lamp timer control settings can be changed with CONSULT-II.
Ignition keyhole illumination turns ON when front door LH is opened (door switch ON) or key is removed from
key cylinder. Illumination turns OFF when front door LH is closed (door switch OFF).
Step and foot lamp turns ON when front or rear doors are opened (door switch ON). Lamp turns OFF when
front and rear doors are closed (all door switches OFF).
POWER SUPPLY AND GROUND
Power is supplied at all times

through 10A fuse [No. 19, located in the fuse block (J/B)]

to key switch and key lock solenoid terminal 3, and

through 15A fuse [No. 22, located in the fuse block (J/B)]

to BCM terminal 57, and

through 50A fusible link (letter f , located in the fuse and fusible link box)

to BCM terminal 70.
When the key is inserted in key switch and key lock solenoid, power is supplied

through the key switch and key lock solenoid terminal 4

to BCM terminal 37.
With the ignition switch in the ON or START position, power is supplied

through 10A fuse (No. 59, located in the fuse and relay box)

to BCM terminal 38.
Ground is supplied

to BCM terminal 67

through grounds M57, M61 and M79.
When the front door LH is opened, ground is supplied

to BCM terminal 47

through case ground of front door switch LH.
When the front door RH is opened, ground is supplied

to BCM terminal 12

through case ground of front door switch RH.
When the rear door LH is opened, ground is supplied

to BCM terminal 48

through case ground of rear door switch LH.
When the rear door RH is opened, ground is supplied

to BCM terminal 13

through case ground of rear door switch RH.
When the liftgate is opened, ground is supplied

to BCM terminal 43

through back door latch (door ajar switch) terminal 7

through back door latch (door ajar switch) terminal 8

through grounds B7 and B19.
When the glass hatch is opened, ground is supplied

to BCM terminal 42

through case ground of glass hatch ajar switch.

INTERIOR ROOM LAMP
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When the front door LH or RH is unlocked by the door lock and unlock switch, BCM receives serial data

to BCM terminal 22

through main power window and door lock/unlock switch terminal 14 or power window and door lock/
unlock switch RH terminal 16

through main power window and door lock/unlock switch terminal 17 or power window and door lock/
unlock switch RH terminal 11

through grounds M57, M61 and M79.
When the front door LH is unlocked by the key, the BCM receives serial data

to BCM terminal 22

through main power window and door lock/unlock switch terminal 14

through main power window and door lock/unlock switch terminal 6

through front door lock assembly LH (key cylinder switch) terminal 6

through front door lock assembly LH (key cylinder switch) terminal 5

through grounds M57, M61 and M79.
When a signal, or combination of signals is received by BCM, ground is supplied

to door mirror LH and RH terminal 13

to front room/map lamp assembly terminal 1

through front room/map lamp assembly terminal 2

to personal lamps terminal 1

through BCM terminal 63, and

to cargo lamp terminal 1

through BCM terminal 49.
With power and ground supplied, the lamps illuminate.
SWITCH OPERATION
When any door switch is ON (door is opened), ground is supplied

to front and rear step lamps LH and RH and foot lamp LH and RH terminal –

through BCM terminal 62.
And power is supplied

through BCM terminal 56

to front and rear step lamps LH and RH terminal +

to ignition keyhole illumination terminal +

to door mirror LH and RH terminal 12

to front room/map lamp assembly terminal 6

to vanity lamps terminal 1

to personal lamps terminal 3

to cargo lamp terminal 2, and

to foot lamp LH and RH terminal +.
When map lamp switch is ON, ground is supplied

to front room/map lamp assembly terminal 5

through grounds M57, M61 and M79.
When vanity lamp (LH and RH) is ON, ground is supplied

to vanity lamp (LH and RH) terminal 2

through grounds M57, M61 and M79.
When cargo lamp is ON, ground is supplied through cargo lamp case ground.
ROOM LAMP TIMER OPERATION
When lamp switch is in DOOR position, and when all conditions below are met, BCM performs timer control
(maximum 30 seconds) for interior room lamp and map lamp ON/OFF.
Power is supplied

through 10A fuse [No. 19, located in the fuse block (J/B)]

INTERIOR ROOM LAMP
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Preliminary CheckEKS007D3
INSPECTION FOR POWER SUPPLY AND GROUND CIRCUIT
1. CHECK FUSES OR FUSIBLE LINK
Check for blown BCM fuses or fusible link.
Refer to LT-135, "
Wiring Diagram — INT/L —" .
OK or NG
OK >> GO TO 2.
NG >> If fuse is blown, be sure to eliminate cause of blown fuse before installing new fuse. Refer to PG-
4, "POWER SUPPLY ROUTING CIRCUIT" .
2. CHECK POWER SUPPLY CIRCUIT
1. Disconnect BCM connectors.
2. Check voltage between BCM connector and ground.
OK or NG
OK >> GO TO 3.
NG >> Check harness for open between BCM and fuse or fusible link.
3. CHECK GROUND CIRCUIT
Check continuity between BCM and ground.
OK or NG
OK >> Inspection End.
NG >> Check harness ground circuit.
Unit Power source Fuse or fusible link No.
BCMBatteryf
22
Ignition switch ON or START position 59
BCM
(–)Ignition switch position
(+)
OFF ON
ConnectorTerminal
(wire color)
M2057 (Y/R)
GroundBattery voltage Battery voltage
70 (W/B) Battery voltage Battery voltage
M18 38 (W/L) 0V Battery voltage
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BCM
Continuity
ConnectorTe r m i n a l
(wire color)
M20 67 (B) Ground Yes
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LT-152
ILLUMINATION
Revision: August 20072004 QX56
ILLUMINATIONPFP:27545
Component Parts and Harness Connector LocationEKS007D9
System DescriptionEKS007DA
Control of the illumination lamps operation is dependent upon the position of the lighting switch (combination
switch). When the lighting switch is placed in the 1ST or 2ND position (or if the auto light system is activated)
the BCM (body control module) receives input signal requesting the illumination lamps to illuminate. This input
signal is communicated to the IPDM E/R (intelligent power distribution module engine room) across the CAN
communication lines. The CPU (central processing unit) of the IPDM E/R controls the tail lamp relay coil. This
relay, when energized, directs power to the illumination lamps, which then illuminate.
Power is supplied at all times

to tail lamp relay, located in the IPDM E/R, and

through 50A fusible link (letter f , located in the fuse and fusible link box)

to BCM terminal 70, and

through 20A fuse (No. 53, located in the IPDM E/R)

to CPU of the IPDM E/R, and

through 10A fuse [No.19, located in fuse block (J/B)]

to combination meter terminal 8, and
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ILLUMINATION
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to ignition relay, located in the IPDM E/R.
With the ignition switch in the ON or START position, power is supplied

through 10A fuse (No. 59, located in the fuse and relay box)

to BCM terminal 38, and

to ignition relay in the IPDM E/R, and

through 10A fuse [No. 14, located in the fuse block (J/B)]

to combination meter terminal 24.
Ground is supplied

to BCM terminal 67 and

to combination meter terminal 17

through grounds M57, M61 and M79, and

to IPDM E/R terminals 38 and 59

through grounds E9, E15 and E24.
ILLUMINATION OPERATION BY LIGHTING SWITCH
With the lighting switch in the 1ST or 2ND position (or if the auto light system is activated), the BCM receives
input signal requesting the illumination lamps to illuminate. This input signal is communicated to the IPDM E/R
across the CAN communication lines. The CPU of the IPDM E/R controls the tail lamp relay coil, which, when
energized, directs power

through 10A fuse (No. 36, located in the IPDM E/R)

through IPDM E/R terminal 49

to illumination control switch terminal 1

to power liftgate switch terminal 3

to front room/map lamp assembly (console box illumination) terminal 7

to hazard switch terminal 3

to rear sonar system OFF switch terminal 3

to glove box lamp terminal +

to display control unit terminal 14

to 4WD shift switch terminal 7 (with 4-wheel drive)

to front air control terminal 23

to rear power vent window switch terminal 5

to DVD player terminal 12 (with DVD entertainment system)

to NAVI control unit terminal 25

to pedal adjusting switch terminal 5

to electric brake (pre-wiring) terminal 4

to heated seat switches terminal 5

to A/T device terminal 11

to VDC OFF switch terminal 3

to tow mode switch terminal 3

to headlamp aiming switch terminal 3

to clock terminal 3

to compass and thermometer terminal 4, and

through 10A fuse (No. 37, located in the IPDM E/R)

through IPDM E/R terminal 57

to AV switch terminal 3

to audio unit terminal 8

to rear air control terminal 1 and

to rear audio remote control unit terminal 6.
Illumination is controlled

through illumination control switch terminal 2

PG-1
POWER SUPPLY, GROUND & CIRCUIT ELEMENTS
K ELECTRICAL
CONTENTS
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Revision: August 20072004 QX56 PRECAUTIONS .......................................................... 3
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 3
Wiring Diagrams and Trouble Diagnosis .................. 3
POWER SUPPLY ROUTING CIRCUIT ...................... 4
Schematic ................................................................ 4
Wiring Diagram — POWER — ................................. 6
BATTERY POWER SUPPLY — IGNITION SW.
IN ANY POSITION ................................................ 6
ACCESSORY POWER SUPPLY — IGNITION
SW. IN ACC OR ON .............................................11
IGNITION POWER SUPPLY — IGNITION SW.
IN ON .................................................................. 12
IGNITION POWER SUPPLY — IGNITION SW.
IN ON AND/OR START ....................................... 13
IPDM E/R (INTELLIGENT POWER DISTRIBUTION
MODULE ENGINE ROOM) ...................................... 17
System Description ................................................ 17
SYSTEMS CONTROLLED BY IPDM E/R ........... 17
CAN COMMUNICATION LINE CONTROL ......... 17
IPDM E/R STATUS CONTROL ........................... 18
CAN Communication System Description .............. 18
Function of Detecting Ignition Relay Malfunction ... 18
CONSULT-II Function (IPDM E/R) ......................... 19
CONSULT-II BASIC OPERATION ...................... 19
SELF-DIAGNOSTIC RESULTS .......................... 20
DATA MONITOR ................................................. 20
ACTIVE TEST ..................................................... 22
Auto Active Test ..................................................... 23
DESCRIPTION .................................................... 23
OPERATION PROCEDURE ............................... 23
INSPECTION IN AUTO ACTIVE TEST MODE ... 23
Schematic .............................................................. 25
IPDM E/R Terminal Arrangement ........................... 26
IPDM E/R Power/Ground Circuit Inspection .......... 27
Inspection with CONSULT-II (Self-Diagnosis) ........ 28
Removal and Installation of IPDM E/R ................... 29
REMOVAL ........................................................... 29
INSTALLATION ................................................... 29GROUND CIRCUIT ................................................... 30
Ground Distribution ................................................. 30
MAIN HARNESS ................................................. 30
ENGINE ROOM HARNESS ................................ 33
ENGINE CONTROL HARNESS .......................... 36
BODY HARNESS ................................................ 37
BODY NO. 2 HARNESS ..................................... 38
BACK DOOR NO. 2 RH HARNESS .................... 39
HARNESS ................................................................. 40
Harness Layout ...................................................... 40
HOW TO READ HARNESS LAYOUT ................. 40
OUTLINE ............................................................. 41
MAIN HARNESS ................................................. 42
ENGINE ROOM HARNESS (LH VIEW) .............. 44
ENGINE ROOM HARNESS (RH VIEW) ............. 47
ENGINE CONTROL HARNESS .......................... 49
CHASSIS HARNESS .......................................... 51
BODY HARNESS ................................................ 53
BODY NO. 2 HARNESS ..................................... 55
ROOM LAMP HARNESS .................................... 57
FRONT DOOR LH HARNESS ............................ 58
FRONT DOOR RH HARNESS ............................ 58
REAR DOOR LH HARNESS ............................... 59
REAR DOOR RH HARNESS .............................. 59
BACK DOOR HARNESS .................................... 60
Wiring Diagram Codes (Cell Codes) ...................... 61
ELECTRICAL UNITS LOCATION ............................ 64
Electrical Units Location ......................................... 64
ENGINE COMPARTMENT .................................. 64
PASSENGER COMPARTMENT ......................... 65
Fuse ........................................................................ 67
Fusible Link ............................................................ 67
Circuit Breaker (Built Into BCM) ............................. 67
HARNESS CONNECTOR ......................................... 68
Description .............................................................. 68
HARNESS CONNECTOR (TAB-LOCKING
TYPE) .................................................................. 68
HARNESS CONNECTOR (SLIDE-LOCKING
TYPE) .................................................................. 69
HARNESS CONNECTOR (DIRECT-CONNECT