Can communication INFINITI QX56 2004 Factory Service Manual

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PARKING, LICENSE PLATE AND TAIL LAMPS
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PARKING, LICENSE PLATE AND TAIL LAMPSPFP:26550
Component Parts and Harness Connector LocationEKS007CD
System DescriptionEKS007CE
Control of the parking, license plate, and tail lamp operation is dependent upon the position of the lighting
switch (combination switch). When the lighting switch is placed in the 1ST position, the BCM (body control
module) receives input signal requesting the parking, license plate, side marker and tail 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 parking, license plate and tail lamps, which then illumi-
nate.
Power is supplied at all times

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

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

to CPU of the IPDM E/R, and

to ignition 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.
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, located in the IPDM E/R.
Ground is supplied

to BCM terminal 67

through grounds M57, M61 and M79, and

to IPDM E/R terminals 38 and 59

through grounds E9, E15 and E24.
WKIA3397E

PARKING, LICENSE PLATE AND TAIL LAMPS
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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 parking, license plate, side marker and tail lamps to illuminate. This input signal is
communicated to the IPDM E/R across the CAN communication lines. The CPU in the IPDM E/R controls the
tail lamp relay coil, which when energized, directs power

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

through IPDM E/R terminal 57

to front combination lamp LH and RH terminal 3

to license plate lamps terminal +

to rear combination lamp LH and RH terminal 3.
Ground is supplied

to front combination lamp LH and RH terminal 4

through grounds E9, E15 and E24, and

to rear combination lamp LH terminal 1

through grounds B7 and B19, and

to rear combination lamp RH terminal 1 and

to license plate lamps terminal –

through grounds B117 and B132.
With power and ground supplied, the parking, license plate and tail lamps illuminate.
COMBINATION SWITCH READING FUNCTION
Refer to BCS-3, "COMBINATION SWITCH READING FUNCTION" .
EXTERIOR LAMP BATTERY SAVER CONTROL
When the combination switch (lighting switch) is in the 1ST (or 2ND) position, and the ignition switch is turned
from ON or ACC to OFF, the battery saver control feature is activated.
Under this condition, the parking, license and tail lamps remain illuminated for 5 minutes, then the parking,
license plate and tail lamps are turned off.
Exterior lamp battery saver control mode can be changed by the function setting of CONSULT-II.
CAN Communication System DescriptionEKS007CF
Refer to LAN-5, "CAN COMMUNICATION" .

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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.

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INTERIOR ROOM LAMP
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CONSULT-II Function (BCM)EKS007D4
CONSULT-II can display each diagnostic item using the diagnostic test modes shown following.
CONSULT-II OPERATION
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carries out CAN communication.
1. With the ignition switch OFF, connect CONSULT-II and CON-
SULT-II CONVERTER to the data link connector, then turn igni-
tion switch ON.
2. Touch “START (NISSAN BASED VHCL)”.
3. Touch “BCM” on “SELECT SYSTEM” screen.
If “BCM” is not indicated, go to GI-39, "
CONSULT-II Data Link
Connector (DLC) Circuit" .
BCM diagnostic
test itemDiagnostic mode Description
Inspection by partWORK SUPPORTSupports inspections and adjustments. Commands are transmitted to the BCM
for setting the status suitable for required operation, input/output signals are
received from the BCM and received data is displayed.
DATA MONITOR Displays BCM input/output data in real time.
ACTIVE TEST Operation of electrical loads can be checked by sending drive signal to them.
SELF-DIAG RESULTS Displays BCM self-diagnosis results.
CAN DIAG SUPPORT MNTR The result of transmit/receive diagnosis of CAN communication can be read.
ECU PART NUMBER BCM part number can be read.
CONFIGURATION Performs BCM configuration read/write functions.
BBIA0369E
BCIA0029E
BCIA0030E

LT-152
ILLUMINATION
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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
WKIA3399E

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

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ILLUMINATION
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to power liftgate switch terminal 4

to front room/map lamp assembly (console box illumination) terminal 8

to AV switch terminal 4

to hazard switch terminal 4

to audio unit terminal 7

to rear sonar system OFF switch terminal 4

to 4WD switch terminal 8 (with 4-wheel drive)

to front air control terminal 24 and

to rear power vent window switch terminal 6

to DVD player terminal 10 (with DVD entertainment system)

to pedal adjusting switch terminal 6

to A/T device terminal 12

to front heated seat switches terminal 6

to VDC OFF switch terminal 4

to tow mode switch terminal 4

to headlamp aiming switch terminal 4

to clock terminal 4 and

to combination meter terminal 18.
Ground is supplied

to illumination control switch terminal 3

to glove box lamp terminal –

to display control unit terminal 3

to rear heated seat switches terminal 6

to electric brake (pre-wiring) terminal 1 and

to compass and thermometer terminal 7

through grounds M57, M61 and M79, and

to NAVI control unit terminal 30

to rear air control terminal 3 and

to rear audio remote control unit terminal 15

through grounds B117 and B132.
With power and ground supplied, illumination lamps illuminate.
EXTERIOR LAMP BATTERY SAVER CONTROL
When the combination switch (lighting switch) is in the 1ST or 2ND position (or if auto light system is acti-
vated), and the ignition switch is turned from ON or ACC to OFF, the battery saver control function is activated.
Under this condition, the illumination lamps remain illuminated for 5 minutes, then the illumination lamps are
turned off.
When the lighting switch is turned from OFF to 1ST or 2ND position (or if auto light system is activated) after
illumination lamps are turned off by the battery saver control, the illumination lamps illuminate again.
Exterior lamp battery saver control mode can be changed by the function setting of CONSULT-II.
CAN Communication System DescriptionEKS007DB
Refer to LAN-5, "CAN COMMUNICATION" .

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

IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
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IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
PFP:284B7
System DescriptionEKS007NN

IPDM E/R (Intelligent Power Distribution Module Engine Room) integrates the relay box and fuse block
which were originally placed in engine compartment. It controls integrated relays via IPDM E/R control cir-
cuits.

IPDM E/R-integrated control circuits perform ON-OFF operation of relays, CAN communication control,
etc.

It controls operation of each electrical component via ECM, BCM and CAN communication lines.
CAUTION:
None of the IPDM E/R integrated relays can be removed.
SYSTEMS CONTROLLED BY IPDM E/R
1. Lamp control
Using CAN communication lines, it receives signals from the BCM and controls the following lamps:

Headlamps (Hi, Lo)

Parking lamps

Tail lamps

Front fog lamps
2. Wiper control
Using CAN communication lines, it receives signals from the BCM and controls the front wipers.
3. Rear window defogger relay control
Using CAN communication lines, it receives signals from the BCM and controls the rear window defogger
relay.
4. A/C compressor control
Using CAN communication lines, it receives signals from the ECM and controls the A/C compressor
(magnetic clutch).
5. Starter control
Using CAN communication lines, it receives signals from the ECM and controls the starter relay.
6. Cooling fan control
Using CAN communication lines, it receives signals from the ECM and controls the cooling fan relays.
7. Horn control
Using CAN communication lines, it receives signals from the BCM and controls the horn relay.
CAN COMMUNICATION LINE CONTROL
With CAN communication, by connecting each control unit using two communication lines (CAN L-line, CAN
H-line), it is possible to transmit a maximum amount of information with minimum wiring. Each control unit can
transmit and receive data, and reads necessary information only.
1. Fail-safe control

When CAN communication with other control units is impossible, IPDM E/R performs fail-safe control.
After CAN communication returns to normal operation, it also returns to normal control.

Operation of control parts by IPDM E/R during fail-safe mode is as follows:
Controlled system Fail-safe mode
Headlamp

With the ignition switch ON, the headlamp (low) is ON.

With the ignition switch OFF, the headlamp (low) is OFF.
Tail and parking lamps

With the ignition switch ON, the tail and parking lamps are ON.

With the ignition switch OFF, the tail and parking lamps are OFF.
Cooling fan

With the ignition switch ON, the cooling fan HI operates.

With the ignition switch OFF, the cooling fan stops.
Front wiperUntil the ignition switch is turned off, the front wiper LO and HI remains in the same status it
was in just before fail−safe control was initiated.
Rear window defogger Rear window defogger relay OFF

PG-18
IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
Revision: August 20072004 QX56
IPDM E/R STATUS CONTROL
In order to save power, IPDM E/R switches status automatically based on each operating condition.
1. CAN communication status

CAN communication is normally performed with other control units.

Individual unit control by IPDM E/R is normally performed.

When sleep request signal is received from BCM, mode is switched to sleep waiting status.
2. Sleep waiting status

Process to stop CAN communication is activated.

All systems controlled by IPDM E/R are stopped. When 1 second has elapsed after CAN communica-
tion with other control units is stopped, mode switches to sleep status.
3. Sleep status

IPDM E/R operates in low current-consumption mode.

CAN communication is stopped.

When a change in CAN communication signal is detected, mode switches to CAN communication sta-
tus.

When a change in ignition switch signal is detected, mode switches to CAN communication status.
CAN Communication System DescriptionEKS007NO
Refer to LAN-5, "CAN COMMUNICATION" .
Function of Detecting Ignition Relay MalfunctionEKS007NP

When the integrated ignition relay is stuck in a "closed contact" position and cannot be turned OFF, IPDM
E/R turns ON tail and parking lamps for 10 minutes to indicate IPDM E/R malfunction.

When the state of the integrated ignition relay does not agree with the state of the ignition switch signal
received via CAN communication, the IPDM E/R activates the tail lamp relay.
NOTE:
When the ignition switch is turned ON, the tail lamps are OFF.
A/C compressor A/C compressor OFF
Front fog lamps Front fog lamp relay OFFControlled system Fail-safe mode
Ignition switch signal Ignition relay status Tail lamp relay
ON ON —
OFF OFF —
ON OFF —
OFF ON ON (10 minutes)