2007 INFINITI QX56 service

LAN-74
< SERVICE INFORMATION >[CAN]
TROUBLE DIAGNOSIS
ABS Actuator and Electric Unit (Control Unit) Branch Line Circuit
INFOID:0000000003533658
INSPECTION PROCEDURE
1.CHECK CONNECTOR
1. Turn the ignition switch OFF.
2. Disconnect the battery cable from the negative terminal.
3. Check the terminals and connectors of the ABS actuator and electric unit (control unit) for damage, bend
and loose connection (unit side and connector side).
OK or NG
OK >> GO TO 2.
NG >> Repair the terminal and connector.
2.CHECK HARNESS FOR OPEN CIRCUIT
1. Disconnect the connector of ABS actuator and electric unit (control unit).
2. Check the resistance between the ABS actuator and electric unit (control unit) harness connector termi-
nals.
OK or NG
OK >> GO TO 3.
NG >> Repair the ABS actuator and electric unit (control unit) branch line.
3.CHECK POWER SUPPLY AND GROUND CIRCUIT
Check the power supply and the ground circuit of the ABS actuator and electric unit (control unit). Refer to
BRC-15, "
Schematic".
OK or NG
OK >> • Present error: Replace the ABS actuator and electric unit (control unit). Refer to BRC-58,
"Removal and Installation".
• Past error: Error was detected in the ABS actuator and electric unit (control unit) branch line.
NG >> Repair the power supply and the ground circuit.
IPDM E/R Branch Line CircuitINFOID:0000000003533659
INSPECTION PROCEDURE
1.CHECK CONNECTOR
1. Turn the ignition switch OFF.
2. Disconnect the battery cable from the negative terminal.
3. Check the terminals and connectors of the IPDM E/R for damage, bend and loose connection (unit side
and connector side).
OK or NG
OK >> GO TO 2.
NG >> Repair the terminal and connector.
2.CHECK HARNESS FOR OPEN CIRCUIT
1. Disconnect the connector of IPDM E/R.
2. Check the resistance between the IPDM E/R harness connector terminals.
OK or NG
OK >> GO TO 3.
ABS actuator and electric unit (control unit) harness connector
Resistance (Ω)
Connector No. Terminal No.
E125 11 15 Approx. 54 – 66
IPDM E/R harness connector
Resistance (Ω)
Connector No. Terminal No.
E122 39 40 Approx. 108 – 132

TROUBLE DIAGNOSIS
LAN-75
< SERVICE INFORMATION >[CAN]
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NG >> Repair the IPDM E/R branch line.
3.CHECK POWER SUPPLY AND GROUND CIRCUIT
Check the power supply and the ground circuit of the IPDM E/R. Refer to PG-3, "
Schematic".
OK or NG
OK >> • Present error: Replace the IPDM E/R. Refer to PG-28, "Removal and Installation of IPDM E/R".
• Past error: Error was detected in the IPDM E/R branch line.
NG >> Repair the power supply and the ground circuit.
CAN Communication CircuitINFOID:0000000003533660
INSPECTION PROCEDURE
1.CONNECTOR INSPECTION
1. Turn the ignition switch OFF
2. Disconnect the battery cable from the negative terminal.
3. Disconnect all the unit connectors on CAN communication system.
4. Check terminals and connectors for damage, bend and loose connection.
OK or NG
OK >> GO TO 2.
NG >> Repair the terminal and connector.
2.CHECK HARNESS CONTINUITY (SHORT CIRCUIT)
Check the continuity between the data link connector terminals.
OK or NG
OK >> GO TO 3.
NG >> Check the harness and repair the root cause.
3.CHECK HARNESS CONTINUITY (SHORT CIRCUIT)
Check the continuity between the data link connector and the ground.
OK or NG
OK >> GO TO 4.
NG >> Check the harness and repair the root cause.
4.CHECK ECM AND IPDM E/R TERMINATION CIRCUIT
1. Remove the ECM and the IPDM E/R.
2. Check the resistance between the ECM terminals.
3. Check the resistance between the IPDM E/R terminals.
Data link connector
Continuity
Connector No. Terminal No.
M22 6 14 No
Data link connector
GroundContinuity
Connector No. Terminal No.
M226No
14 No
ECM
Resistance (Ω)
Te r m i n a l N o .
94 86 Approx. 108 – 132
LKIA0037E

LAN-76
< SERVICE INFORMATION >[CAN]
TROUBLE DIAGNOSIS
OK or NG
OK >> GO TO 5.
NG >> Replace the ECM and/or the IPDM E/R.
5.CHECK SYMPTOM
Connect all the connectors. Check if the symptoms described in the “Symptom (Results from interview with
customer)” are reproduced.
Inspection result
Reproduced>>GO TO 6.
Non-reproduced>>Start the diagnosis again. Follow the trouble diagnosis procedure when past error is
detected.
6.CHECK UNIT REPRODUCTION
Perform the reproduction test as per the following procedure for each unit.
1. Turn the ignition switch OFF
2. Disconnect the battery cable from the negative terminal.
3. Disconnect all the unit connectors on CAN communication system.
NOTE:
ECM and IPDM E/R have a termination circuit. Check other units first.
4. Connect the battery cable to the negative terminal. Check if the symptoms described in the “Symptom
(Results from interview with customer)” are reproduced.
NOTE:
Although unit-related error symptoms occur, do not confuse them with other symptoms.
Inspection result
Reproduced>>Connect the connector. Check other units as per the above procedure.
Non-reproduced>>Replace unit whose connector was disconnected.
IPDM E/R
Resistance (Ω)
Te r m i n a l N o .
39 40 Approx. 108 – 132

LT-1
ELECTRICAL
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SECTION LT
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CONTENTS
LIGHTING SYSTEM
SERVICE INFORMATION ............................4
PRECAUTIONS ...................................................4
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ...................................................................
4
General precautions for service operations ..............4
HEADLAMP (FOR USA) .....................................5
Component Parts and Harness Connector Loca-
tion ............................................................................
5
System Description ...................................................5
CAN Communication System Description .................7
Schematic .................................................................7
Wiring Diagram - H/LAMP - .......................................8
Terminal and Reference Value for BCM .................11
Terminal and Reference Value for IPDM E/R .........11
How to Proceed with Trouble Diagnosis .................12
Preliminary Check ...................................................12
CONSULT-II Function (BCM) ..................................12
CONSULT-II Function (IPDM E/R) ..........................13
Headlamp HI Does Not Illuminate (Both Sides) ......14
Headlamp HI Does Not Illuminate (One Side) ........15
High Beam Indicator Lamp Does Not Illuminate .....16
Headlamp LO Does Not Illuminate (Both Sides) .....17
Headlamp LO Does Not Illuminate (One Side) .......18
Headlamps Do Not Turn OFF .................................19
Aiming Adjustment ..................................................20
Bulb Replacement ...................................................21
Removal and Installation .........................................22
Disassembly and Assembly ....................................23
HEADLAMP (FOR CANADA) - DAYTIME
LIGHT SYSTEM - ...............................................
24
Component Parts and Harness Connector Loca-
tion ..........................................................................
24
System Description .................................................24
CAN Communication System Description ...............25
Schematic ...............................................................26
Wiring Diagram - DTRL - .........................................27
Terminal and Reference Value for BCM .................30
How to Proceed with Trouble Diagnosis ..................30
Preliminary Check ...................................................31
CONSULT-II Function for BCM ...............................32
CONSULT-II Function for IPDM E/R .......................32
Daytime Light Control Does Not Operate Properly
(Normal Headlamps Operate Properly) ...................
32
Aiming Adjustment ...................................................33
Bulb Replacement ...................................................33
Removal and Installation .........................................33
Disassembly and Assembly .....................................33
AUTO LIGHT SYSTEM .....................................34
Component Parts and Harness Connector Loca-
tion ...........................................................................
34
System Description ..................................................34
CAN Communication System Description ...............35
Major Component and Functions ............................35
Schematic ................................................................36
Wiring Diagram - AUTO/L - .....................................37
Terminal and Reference Value for BCM ..................39
Terminal and Reference Value for IPDM E/R ..........39
How to Proceed with Trouble Diagnosis ..................40
Preliminary Check ...................................................40
CONSULT-II Function (BCM) ..................................40
CONSULT-II Function (IPDM E/R) ..........................41
Trouble Diagnosis Chart by Symptom .....................42
Lighting Switch Inspection .......................................42
Optical Sensor System Inspection ...........................43
Optical Sensor .........................................................44
HEADLAMP AIMING CONTROL ......................45
System Description ..................................................45
Wiring Diagram - H/AIM - ........................................46
Headlamp Aiming Switch .........................................47
Switch Circuit Inspection .........................................48
FRONT FOG LAMP ..........................................49
Component Parts and Harness Connector Loca-
tion ...........................................................................
49
System Description ..................................................49
CAN Communication System Description ...............50

LT-4
< SERVICE INFORMATION >
PRECAUTIONS
SERVICE INFORMATION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000003533330
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SRS and SB section of this Service Man-
ual.
WARNING:
• To 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 NISSAN/INFINITI dealer.
• Improper maintenance, including incorrect removal and installation of the SRS, can lead to personal
injury caused by unintentional activation of the system. For removal of Spiral Cable and Air Bag
Module, see the SRS section.
• Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or har-
ness connectors.
General precautions for service operationsINFOID:0000000003533331
• Never work with wet hands.
• Xenon headlamp includes high voltage generating part. Be sure to
disconnect battery negative cable (negative terminal) or power
fuse before removing, installing, or touching the xenon headlamp
(including lamp bulb).
• Turn the lighting switch OFF before disconnecting and connecting
the connector.
• When turning the xenon headlamp on and while it is illuminated,
never touch the harness, bulb, and socket of the headlamp.
• When checking the headlamp on/off operation, check it on vehicle
and with the power connected to the vehicle-side connector.
• Do not touch the headlamp bulb glass surface with bare hands or
allow oil or grease to get on it. Do not touch the headlamp bulb just after the headlamp is turned off, because
it is very hot.
• Install the xenon headlamp bulb socket correctly. If it is installed
improperly, high-voltage leak or corona discharge may occur that
can melt the bulb, connector, and housing. Do not illuminate the
xenon headlamp bulb out of the headlamp housing. Doing so can
cause fire and harm your eyes.
• When the bulb has burned out, wrap it in a thick vinyl bag and dis-
card. Do not break the bulb.
• Leaving the bulb removed from the headlamp housing for a long
period of time can deteriorate the performance of the lens and
reflector (dirt, clouding). Always prepare a new bulb and have it on
hand when replacing the bulb.
• Do not use organic solvent (paint thinner or gasoline) to clean
lamps and to remove old sealant.
WKIA0460E
EL-3422D

HEADLAMP (FOR USA)
LT-5
< SERVICE INFORMATION >
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HEADLAMP (FOR USA)
Component Parts and Harness Connector LocationINFOID:0000000003533332
System DescriptionINFOID:0000000003533333
Control of the headlamp system operation is dependent upon the position of the combination switch (lighting
switch). When the lighting switch is placed in the 2ND position, the BCM (body control module) receives input
requesting the headlamps (and tail lamps) illuminate. This input 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 headlamp high and headlamp low relay coils. When energized, these relays
direct power to the respective headlamps, which then illuminate.
OUTLINE
Power is supplied at all times
• to ignition relay, located in the IPDM E/R,
• to headlamp high relay, located in the IPDM E/R,
• to headlamp low relay, located in the IPDM E/R,
• through 20A fuse (No. 53, located in the IPDM E/R)
• to CPU of 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
• to ignition relay, located in the IPDM E/R, and
• through 10A fuse (No. 59, located in the fuse and relay box)
WKIA3463E

LT-6
< SERVICE INFORMATION >
HEADLAMP (FOR USA)
• to BCM terminal 38.
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.
Low Beam Operation
With the lighting switch in 2ND position, the BCM receives input requesting the headlamps to illuminate. This
input is communicated to the IPDM E/R across the CAN communication lines. The CPU of the IPDM E/R con-
trols the headlamp low relay coil. When energized, this relay directs power
• through 15A fuse (No. 41, located in the IPDM E/R)
• through IPDM E/R terminal 54
• to front combination lamp RH terminal 5, and
• through 15A fuse (No. 40, located in the IPDM E/R)
• through IPDM E/R terminal 52
• to front combination lamp LH terminal 5.
Ground is supplied
• to front combination lamp LH and RH terminal 1
• through grounds E9, E15 and E24.
With power and ground supplied, low beam headlamps illuminate.
High Beam Operation/Flash-to-Pass Operation
With the lighting switch in 2ND position and placed in HIGH or PASS position, the BCM receives input request-
ing the headlamp high beams to illuminate. This input is communicated to the IPDM E/R across the CAN com-
munication lines. The CPU of the combination meter controls the ON/OFF status of the HIGH BEAM indicator.
The CPU of the IPDM E/R controls the headlamp high relay coil. When energized, this relay directs power
• through 10A fuse (No. 34, located in the IPDM E/R)
• through IPDM E/R terminal 56
• to front combination lamp RH terminal 6, and
• through 10A fuse (No. 35, located in the IPDM E/R)
• through IPDM E/R terminal 55
• to front combination lamp LH terminal 6.
Ground is supplied
• to front combination lamp LH and RH terminal 2
• through grounds E9, E15 and E24.
With power and ground supplied, the high beam headlamps illuminate.
XENON HEADLAMP
Xenon type headlamp is adopted to the low beam headlamps. Xenon bulbs do not use a filament. Instead,
they produce light when a high voltage current is passed between two tungsten electrodes through a mixture
of xenon (an inert gas) and certain other metal halides. In addition to added lighting power, electronic control
of the power supply gives the headlamps stable quality and tone color.
Following are some of the many advantages of the xenon type headlamp.
• The light produced by the headlamps is a white color comparable to sunlight that is easy on the eyes.
• Light output is nearly double that of halogen headlamps, affording increased area of illumination.
• The light features a high relative spectral distribution at wavelengths to which the human eye is most sensi-
tive. This means that even in the rain, more light is reflected back from the road surface toward the vehicle,
for added visibility.
• Power consumption is approximately 25 percent less than halogen headlamps, reducing battery load.
BATTERY SAVER CONTROL
When the combination switch (lighting switch) is in the 2ND position (ON), and the ignition switch is turned
from ON or ACC to OFF, the battery saver control feature is activated.
Under this condition, the headlamps remain illuminated for 5 minutes, unless the combination switch (lighting
switch) position is changed. If the combination switch (lighting switch) position is changed, then the headlamps
are turned off.
AUTO LIGHT OPERATION
Refer to LT-34, "System Description" for auto light operation.
VEHICLE SECURITY SYSTEM (PANIC ALARM)

HEADLAMP (FOR USA)
LT-7
< SERVICE INFORMATION >
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The vehicle security system (panic alarm) will flash the high beams if the system is triggered. Refer to BL-61,
"System Description".
CAN Communication System DescriptionINFOID:0000000003533334
Refer to LAN-4, "CAN Communication System".
SchematicINFOID:0000000003533335
WKWA3637E