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LAN-114
[CAN]
CAN SYSTEM (TYPE 3)
Revision: August 20072004 QX56
Case 16
Check CAN communication circuit. Refer to LAN-124, "CAN Communication Circuit Check" .
Case 17
Check IPDM E/R ignition relay circuit continuously sticks “OFF”. Refer to LAN-124, "IPDM E/R Ignition Relay
Circuit Check" .
PKIA8084E
PKIA8085E
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![INFINITI QX56 2004 Factory Service Manual CAN SYSTEM (TYPE 3)
LAN-115
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Case 18
Check IPDM E/R ignition relay circuit continuously sticks “ON”. Refer to LAN-124, "IPDM E/R Igni INFINITI QX56 2004 Factory Service Manual CAN SYSTEM (TYPE 3)
LAN-115
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Case 18
Check IPDM E/R ignition relay circuit continuously sticks “ON”. Refer to LAN-124, "IPDM E/R Igni](/manual-img/42/57034/w960_57034-2377.png)
CAN SYSTEM (TYPE 3)
LAN-115
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Case 18
Check IPDM E/R ignition relay circuit continuously sticks “ON”. Refer to LAN-124, "IPDM E/R Ignition Relay
Circuit Check" .
Circuit Check Between TCM and Driver Seat Control UnitUKS0019W
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 (connector side and
harness side).
–Harness connector F33
–Harness connector E19
–Harness connector E34
–Harness connector B40
OK or NG
OK >> GO TO 2.
NG >> Repair terminal or connector.
2. CHECK HARNESS FOR OPEN CIRCUIT
1. Disconnect A/T assembly connector and harness connector F33.
2. Check continuity between A/T assembly harness connector F9
terminals 3 (W), 8 (R) and harness connector F33 terminals 12
(W), 11 (R).
OK or NG
OK >> GO TO 3.
NG >> Repair harness.
PKIA8086E
3 (W) - 12 (W) : Continuity should exist.
8 (R) - 11 (R) : Continuity should exist.
PKIA6831E
Page 2387 of 3371
![INFINITI QX56 2004 Factory Service Manual LAN-124
[CAN]
CAN SYSTEM (TYPE 3)
Revision: August 20072004 QX56
CAN Communication Circuit CheckUKS001AB
1. CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect the negative battery terminal.
3. INFINITI QX56 2004 Factory Service Manual LAN-124
[CAN]
CAN SYSTEM (TYPE 3)
Revision: August 20072004 QX56
CAN Communication Circuit CheckUKS001AB
1. CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect the negative battery terminal.
3.](/manual-img/42/57034/w960_57034-2386.png)
LAN-124
[CAN]
CAN SYSTEM (TYPE 3)
Revision: August 20072004 QX56
CAN Communication Circuit CheckUKS001AB
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
–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-125, "ECM/
IPDM E/R INTERNAL CIRCUIT INSPECTION" .
NG >> Repair harness.
IPDM E/R Ignition Relay Circuit CheckUKS001AC
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" .
Ignition power supply circuit. Refer to PG-13, "IGNITION POWER SUPPLY — IGNITION SW. IN ON
AND/OR START" . 6 (W) - 14 (R) : Continuity should not exist.
PKIA2077E
6 (W) - Ground : Continuity should not exist.
14 (R) - Ground : Continuity should not exist.
PKIA2079E
Page 2417 of 3371
LAN-154
[CAN]
CAN SYSTEM (TYPE 4)
Revision: August 20072004 QX56
Case 20
Check CAN communication circuit. Refer to LAN-166, "CAN Communication Circuit Check" .
Case 21
Check IPDM E/R ignition relay circuit continuously sticks “OFF”. Refer to LAN-166, "IPDM E/R Ignition Relay
Circuit Check" .
PKIA8131E
PKIA8132E
Page 2418 of 3371
CAN SYSTEM (TYPE 4)
LAN-155
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Case 22
Check IPDM E/R ignition relay circuit continuously sticks “ON”. Refer to LAN-166, "IPDM E/R Ignition Relay
Circuit Check" .
Circuit Check Between TCM and ICC SensorUKS001NU
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 (connector side and
harness side).
–Harness connector F33
–Harness connector E19
OK or NG
OK >> GO TO 2.
NG >> Repair terminal or connector.
2. CHECK HARNESS FOR OPEN CIRCUIT
1. Disconnect A/T assembly connector and harness connector F33.
2. Check continuity between A/T assembly harness connector F9
terminals 3 (W), 8 (R) and harness connector F33 terminals 12
(W), 11 (R).
OK or NG
OK >> GO TO 3.
NG >> Repair harness.
PKIA8133E
3 (W) - 12 (W) : Continuity should exist.
8 (R) - 11 (R) : Continuity should exist.
PKIA6831E
Page 2429 of 3371
![INFINITI QX56 2004 Factory Service Manual 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. INFINITI QX56 2004 Factory Service Manual 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.](/manual-img/42/57034/w960_57034-2428.png)
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
Page 2437 of 3371

LT-6
HEADLAMP (FOR USA)
Revision: August 20072004 QX56
HEADLAMP (FOR USA)PFP:26010
Component Parts and Harness Connector LocationEKS0079P
System DescriptionEKS0079Q
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 headlamp high relay, located in the IPDM E/R, and
to headlamp low relay, located in the IPDM E/R, and
to ignition 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
through 10A fuse [No. 19, located in the fuse block (J/B)]
WKIA3392E
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HEADLAMP (FOR USA)
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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.