2004 INFINITI QX56 COMBINATION METER

CAN SYSTEM (TYPE 4)
LAN-161
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Driver Seat Control Unit Circuit CheckUKS001NZ
1. CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect the negative battery terminal.
3. Check following terminals and connectors for damage, bend and loose connection (control unit side and
harness side).
–Driver seat control unit connector
–Harness connector P1
–Harness connector B37
OK or NG
OK >> GO TO 2.
NG >> Repair terminal or connector.
2. CHECK HARNESS FOR OPEN CIRCUIT
1. Disconnect driver seat control unit connector.
2. Check resistance between driver seat control unit harness con-
nector P2 terminals 3 (W) and 19 (R).
OK or NG
OK >> Replace driver seat control unit.
NG >> Repair harness between driver seat control unit and har-
ness connector B69.
Combination Meter Circuit CheckUKS001O0
1. CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect the negative battery terminal.
3. Check terminals and connector of combination meter for damage, bend and loose connection (meter side
and harness side).
OK or NG
OK >> GO TO 2.
NG >> Repair terminal or connector.
2. CHECK HARNESS FOR OPEN CIRCUIT
1. Disconnect combination meter connector.
2. Check resistance between combination meter harness connec-
tor M24 terminals 11 (W) and 12 (R).
OK or NG
OK >> Replace combination meter.
NG >> Repair harness between combination meter and data
link connector. 3 (W) - 19 (R) : Approx. 54 - 66Ω
PKIA6842E
11 (W) - 12 (R) : Approx. 54 - 66Ω
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LAN-166
[CAN]
CAN SYSTEM (TYPE 4)
Revision: August 20072004 QX56
CAN Communication Circuit CheckUKS001O9
1. CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect the negative battery terminal.
3. Disconnect the following module and control unit connectors and check terminals for deformation, discon-
nection, looseness or damage.
–ECM
–A/T assembly
–ICC sensor
–ICC unit
–Driver seat control unit
–Combination meter
–Display control unit
–BCM
–Steering angle sensor
–Front air control
–Transfer control unit
–ABS actuator and electric unit (control unit)
–IPDM E/R
OK or NG
OK >> GO TO 2.
NG >> Repair or replace as necessary.
2. CHECK HARNESS FOR SHORT CIRCUIT
With all module and control unit connectors disconnected, check
continuity between data link connector M22 terminals 6 (W) and 14
(R).
OK or NG
OK >> GO TO 3.
NG >> Repair harness.
3. CHECK HARNESS FOR SHORT CIRCUIT
Check continuity between data link connector M22 terminals 6 (W),
14 (R) and ground.
OK or NG
OK >> Check ECM and IPDM E/R. Refer to LAN-167, "ECM/
IPDM E/R INTERNAL CIRCUIT INSPECTION" .
NG >> Repair harness.
IPDM E/R Ignition Relay Circuit CheckUKS001OA
Check the following. If no malfunction is found, replace the IPDM E/R.

IPDM E/R power supply circuit. Refer to PG-27, "IPDM E/R Power/Ground Circuit Inspection" . 6 (W) - 14 (R) : Continuity should not exist.
PKIA2077E
6 (W) - Ground : Continuity should not exist.
14 (R) - Ground : Continuity should not exist.
PKIA2079E

HEADLAMP (FOR USA)
LT-7
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Revision: August 20072004 QX56

to combination meter terminal 8, 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. 14, located in the fuse block (J/B)]

to combination meter terminal 24, and

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

to BCM terminal 38.
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.
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.

LT-26
HEADLAMP (FOR USA)
Revision: August 20072004 QX56
4. INSPECTION BETWEEN IPDM E/R AND HEADLAMPS
1. Disconnect IPDM E/R connector and inoperative headlamp connector.
2. Check continuity between harness connector terminals of IPDM
E/R and harness connector terminals of inoperative headlamp.
OK or NG
OK >> Replace IPDM E/R. Refer to PG-29, "Removal and
Installation of IPDM E/R" .
NG >> Check for short circuits and open circuits in harness between IPDM E/R and headlamps. Repair
as necessary.
High Beam Indicator Lamp Does Not IlluminateEKS007A2
1. BULB INSPECTION
Inspect CAN communication system. Refer to LAN-5, "
CAN COMMUNICATION" .
OK or NG
OK >> Replace combination meter. Refer to IP-13, "Combination Meter" .
NG >> Repair as necessary.
Headlamp LO Does Not Illuminate (Both Sides)EKS007A3
1. CHECK COMBINATION SWITCH INPUT SIGNAL
Select “BCM” on CONSULT-II. With “HEAD LAMP” data monitor,
make sure “HEAD LAMP SW 1” and "HEAD LAMP SW 2" turns ON-
OFF linked with operation of lighting switch.
OK or NG
OK >> GO TO 2.
NG >> Check lighting switch. Refer to LT-100, "
Combination
Switch Inspection" .
2. HEADLAMP ACTIVE TEST
1. Select “IPDM E/R” on CONSULT-II, and select “ACTIVE TEST”
on “SELECT DIAG MODE” screen.
2. Select “EXTERNAL LAMPS” on “SELECT TEST ITEM” screen.
3. Touch “LO” on "ACTIVE TEST" screen.
4. Make sure headlamp low beam operates.
OK or NG
OK >> GO TO 3.
NG >> GO TO 4.
IPDM E/R Front combination lamp
Continuity
ConnectorTe r m i n a l
(wire color)ConnectorTe r m i n a l
(wire color)
E12356 (L/W) RH E107 6 (L/W)
Ye s
55 (G) LH E11 6 (G)
WKIA1853E
When lighting switch is in
2ND position: HEAD LAMP SW 1 ON
: HEAD LAMP SW 2 ON
WKIA4262E
Headlamp low beam should operate.
WKIA1438E

HEADLAMP (FOR CANADA) - DAYTIME LIGHT SYSTEM -
LT-35
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System DescriptionEKS007AB
Daytime light system turns on daytime light lamps while driving. Daytime light lamps are not turned on if
engine is activated with parking brake applied. Release parking brake to turn on daytime light lamps. The
lamps turn off when lighting switch is in the 2ND position or AUTO position (Headlamp is "ON") and when light-
ing switch is in the PASSING position. (Daytime light lamps are not turned off only by parking brake itself.)
A parking brake signal and engine run or stop signal are sent to BCM (body control module) by CAN commu-
nication line.
OUTLINE
Power is supplied at all times

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

to combination meter terminal 8, and

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

to BCM terminal 70, and

through 10A fuse [No. 45, located in the IPDM E/R (intelligent power distribution module engine room)]

to daytime light relay terminals 2 and 5.
When the ignition switch is in ON or START position, power is supplied

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

to combination meter terminal 24, and

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

to BCM terminal 38.
Ground is supplied

to combination meter terminal 17 and

to BCM terminal 67

through grounds M57, M61 and M79.
DAYTIME LIGHT OPERATION
With the engine running, the lighting switch in the OFF or 1ST position and parking brake released, the IPDM
E/R receives input requesting the daytime lights illuminate. This input is communicated across the CAN com-
munication lines. The CPU (central processing unit) of the IPDM E/R controls the daytime light relay coil.
When energized, this relay directs power

through daytime light relay terminal 3

to front combination lamp LH terminal 2

through front combination lamp LH terminal 6

through IPDM E/R terminal 55

through 10A fuse (No. 35, located in the IPDM E/R)

through 10A fuse (No. 34, located in the IPDM E/R)

through IPDM E/R terminal 56

to front combination lamp RH terminal 6.
Ground is supplied

to combination lamp RH terminal 2

through grounds E9, E15 and E24.
With power and ground supplied, the daytime lights illuminate. The high beam headlamps are now wired in
series and illuminate at a reduced intensity.
COMBINATION SWITCH READING FUNCTION
Refer to BCS-3, "COMBINATION SWITCH READING FUNCTION" .
AUTO LIGHT OPERATION
For auto light operation, refer to LT-4 8, "System Description" in AUTO LIGHT SYSTEM.
CAN Communication System DescriptionEKS007AC
Refer to LAN-5, "CAN COMMUNICATION" .

HEADLAMP (FOR CANADA) - DAYTIME LIGHT SYSTEM -
LT-43
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2. CHECK POWER SUPPLY CIRCUIT
1. Disconnect BCM connectors.
2. Check voltage between BCM harness connector and ground.
OK or NG
OK >> GO TO 3.
NG >> Check harness for open or short between BCM and fuse
or fusible link.
3. CHECK GROUND CIRCUIT
Check continuity between BCM harness connector and ground.
OK or NG
OK >> Inspection End.
NG >> Check ground circuit harness.
INSPECTION PARKING BRAKE SWITCH CIRCUIT
1. CHECK BRAKE INDICATOR
1. Turn ignition switch ON.
2. Apply parking brake.
3. Release parking brake.
OK or NG
OK >> Inspection End.
NG >> GO TO 2.
BCM
(–)Ignition switch position
(+)
OFF ACC ON
ConnectorTerminal
(wire color)
M18 38 (W/L)
Ground0V 0VBattery
voltage
M20 70 (W/B)Battery
voltageBattery
voltageBattery
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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Brake indicator in combination meter should illuminate
when parking brake is applied and turn OFF when
released.

LT-44
HEADLAMP (FOR CANADA) - DAYTIME LIGHT SYSTEM -
Revision: August 20072004 QX56
2. CHECK PARKING BRAKE SWITCH SIGNAL
1. Disconnect parking brake switch connector.
2. Turn ignition switch ON.
3. Check voltage between parking brake switch harness connector
M11 terminal + (G) and ground.
OK or NG
OK >> Replace parking brake switch.
NG >> GO TO 3.
3. CHECK PARKING BRAKE SWITCH CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect combination meter connector.
3. Check continuity between combination meter harness connector
M24 terminal 23 (G) and parking brake switch harness connec-
tor M11 terminal + (G).
OK or NG
OK >> Replace combination meter. Refer to IP-13, "Combina-
tion Meter" .
NG >> Repair harness or connector.
CONSULT-II FunctionsEKS007AI
Refer to LT- 1 8 , "CONSULT-II Function (BCM)" in HEADLAMP (FOR USA).
Refer to LT- 2 1 , "
CONSULT-II Function (IPDM E/R)" in HEADLAMP (FOR USA).
Daytime Light Control Does Not Operate Properly (Normal Headlamps Operate
Properly)
EKS007AJ
1. CHECK DAYTIME LIGHT RELAY POWER SUPPLY CIRCUIT
1. Remove daytime light relay.
2. Check voltage between daytime light relay harness connector
E103 terminals 2 (G), 5 (G) and ground
OK or NG
OK >> GO TO 2.
NG >> Repair harness or connector.+ (G) - Ground : Battery voltage should exist.
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+ (G) - 23 (G) : Continuity should exist.
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2 (G), 5 (G) - Ground : Battery voltage should exist.
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LT-62
AUTO LIGHT SYSTEM
Revision: August 20072004 QX56
Trouble Diagnosis Chart by SymptomEKS007B0
Lighting Switch InspectionEKS007B1
1. CHECK LIGHTING SWITCH INPUT SIGNAL
With CONSULT-II
Select “BCM” on CONSULT-II. With “HEAD LAMP” data monitor,
make sure “AUTO LIGHT SW” turns ON-OFF linked with operation
of lighting switch.
Without CONSULT-II
Refer to LT- 1 0 0 , "
Combination Switch Inspection" .
OK or NG
OK >> Inspection End.
NG >> Check lighting switch. Refer to LT-100, "
Combination
Switch Inspection" .
Headlamp relay (HI, LO) out-
put
LAMPSAllows headlamp relay (HI, LO) to operate by switching operation
(OFF, HI, LO) at your option (Headlamp high beam repeats ON-OFF
every 1 second).
Front fog lamp relay outputAllows fog lamp relay to operate by switching operation ON-OFF at
your option. Test item CONSULT-II screen display Description
Trouble phenomenon Malfunction system and reference

Parking lamps and headlamps will not illuminate when out-
side of the vehicle becomes dark. (Lighting switch 1st posi-
tion and 2nd position operate normally.)

Parking lamps and headlamp will not go out when outside of
the vehicle becomes light. (Lighting switch 1st position and
2nd position operate normally.)

Headlamps go out when outside of the vehicle becomes
light, but parking lamps stay on.

Refer to LT-58, "WORK SUPPORT" .

Refer to LT-62, "Lighting Switch Inspection" .

Refer to LT-63, "Optical Sensor System Inspection" .
If above systems are normal, replace BCM. Refer to BCS-19,
"Removal and Installation of BCM" .
Parking lamps illuminate when outside of the vehicle becomes
dark, but headlamps stay off. (Lighting switch 1st position and
2nd position operate normally.)

Refer to LT-58, "WORK SUPPORT" .

Refer to LT-63, "Optical Sensor System Inspection" .
If above systems are normal, replace BCM. Refer to BCS-19,
"Removal and Installation of BCM" .
Auto light adjustment system will not operate. (Lighting switch
AUTO, 1st position and 2nd position operate normally.)

Refer to LT-63, "Optical Sensor System Inspection" .
If above system is normal, replace BCM. Refer to BCS-19, "
Removal
and Installation of BCM" .
Auto light adjustment system will not operate.

CAN communication line to BCM inspection. Refer to BCS-13,
"CAN Communication Inspection Using CONSULT-II (Self-Diagno-
sis)" .
Shut off delay feature will not operate.

CAN communication line inspection between BCM and combina-
tion meter. Refer to BCS-13, "
CAN Communication Inspection
Using CONSULT-II (Self-Diagnosis)" .

Refer to BL-31, "Door Switch Check" .
If above system is normal, replace BCM. Refer to BCS-19, "
Removal
and Installation of BCM" .
When lighting switch is in
AUTO position: AUTO LIGHT SW ON
SKIA4196E