2004 INFINITI QX56 headlamp

LT-48
AUTO LIGHT SYSTEM
Revision: August 20072004 QX56
System DescriptionEKS007AP
Automatically turns on/off the parking lamps and the headlamps in accordance with ambient light.
Timing for when the lamps turn on/off can be selected using four modes.
OUTLINE
The auto light control system uses an optical sensor that detects outside brightness.
When the lighting switch is in “AUTO” position, it automatically turns on/off the parking lamps and the head-
lamps in accordance with the ambient light. Sensitivity can be adjusted in four steps. For the details of the set-
ting, refer to LT-55, "
SETTING CHANGE FUNCTIONS" .
Optical sensor ground is supplied

to optical sensor terminal 3

through BCM (body control module) terminal 18.
When ignition switch is turned to “ON” position and when outside brightness is darker than prescribed level,
input is supplied

to BCM terminal 58

through optical sensor terminal 4.
The headlamps will then illuminate. For a description of headlamp operation, refer to LT- 6 , "
System Descrip-
tion" .
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 AUTO position, and the ignition switch is turned from
ON or ACC to OFF, and one of the front doors is opened, the battery saver control feature is activated.
Under this condition, the headlamps remain illuminated for 5 minutes, then the headlamps are turned off.
Exterior lamp battery saver control mode can be changed by the function setting of CONSULT-II.
DELAY TIMER FUNCTION
When the ignition switch is ON and auto light switch is ON, the BCM turns on/off the headlamps. In delay timer
function, ignition is OFF, auto light sensor power source is OFF and the headlamps are not turned on/off by the
BCM. On condition that:

when the state of ignition switch ON or ACC is ON and output judgment by auto light function is headlamp
ON changes to ignition switch and ACC are OFF and any door switch is ON, output judgment by BCM
should be headlamp ON for 5 minutes by timer. After time out, output judgment by BCM should be head-
lamp OFF.

when the state of any door switch is turned to ON from OFF while 45 second or 5 minute timer is counting,
timer stops, and restarts counting for 5 minutes, then BCM judges output as headlamp ON. After time out,
BCM judges output as headlamp OFF.

when the state of front door switch (driver side), front door switch (passenger side), rear door switch LH,
rear door switch RH or back door latch (door ajar switch) is ON turns to all door switches are OFF while 45
second or 5 minute timer is counting, timer stops, and restarts counting for 45 seconds, then BCM judges
output as headlamp ON. After timer out, BCM judges output as headlamp OFF.

when the state is ignition switch ON or ACC is ON or auto light switch OFF while timer is counting, timer
stops counting and BCM turns on/off lamps according to headlamp function, front fog lamp function, auto
light function and headlamp battery save function.
Delay timer control mode can be changed by the function setting of CONSULT-II.
CAN Communication System DescriptionEKS007AQ
Refer to LAN-5, "CAN COMMUNICATION" .
Major Components and FunctionsEKS007AR
Components Functions
BCM

Turns on/off circuits of tail light and headlamp according to signals from light sensor, lighting switch
(AUTO), driver door switch, passenger door switch, rear door switch, and ignition switch (ON,
OFF).
Optical sensor

Converts ambient light (lux) to voltage, and sends it to BCM. (Detects lightness of 50 to 1,300 lux)

LT-54
AUTO LIGHT SYSTEM
Revision: August 20072004 QX56
NOTE:
Optical sensor must be completely subjected to work lamp light. If the optical sensor is insufficiently illumi-
nated, the measured value may not satisfy standard.
Terminals and Reference Values for IPDM E/REKS007AV
34 L Combination switch output 3 ONLighting, turn, wiper OFF
Wiper dial position 4
35 O/B Combination switch output 2
ONLighting, turn, wiper OFF
Wiper dial position 4
36 R/W Combination switch output 1
38 W/L Ignition switch (ON) ON — Battery voltage
39 W CAN-H — — —
40 R CAN-L — — —
43 R/BBack door latch (door ajar
switch) signalOFFBack door
latch (door
ajar switch)ON (open) 0V
OFF (closed) Battery voltage
47 SB Front door switch LH signal OFFFront door
switch LH ON (open) 0V
OFF (closed) Battery voltage
48 R/Y Rear door switch LH signal OFFRear door
switch LH ON (open) 0V
OFF (closed) Battery voltage
58 W/R Optical sensor signal ONWhen optical sensor is illumi-
natedLess than 3.5V
Note
When optical sensor is not illumi-
natedGreater than 3.5V
67 B Ground ON — 0V
70 W/B Battery power supply OFF — Battery voltage Te r m i n a l
No.Wire
colorSignal nameMeasuring condition
Reference value
(Approx.) Ignition
switchOperation or condition
SKIA5291E
SKIA5292E
Te r m i n a l
No.Wire color Signal nameMeasuring condition
Reference value
(Approx.) Ignition
switchOperation or condition
38 B Ground ON — 0V
39 W CAN-H — — —
40 R CAN-L — — —
52 L Headlamp low (LH) ONLighting switch
2ND positionOFF 0V
ON Battery voltage
54 R/Y Headlamp low (RH) ONLighting switch
2ND positionOFF 0V
ON Battery voltage
55 G Headlamp high (LH) ONLighting switch
HIGH or PASS
positionOFF 0V
ON Battery voltage

AUTO LIGHT SYSTEM
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*1 USA
*2 Canada
How to Proceed With Trouble DiagnosisEKS007AW
1. Confirm the symptom or customer complaint.
2. Understand operation description and function description. Refer to LT- 4 8 , "
System Description" .
3. Carry out the Preliminary Check. Refer to LT- 5 5 , "
Preliminary Check" .
4. Check symptom and repair or replace the cause of malfunction. Refer to LT- 6 2 , "
Trouble Diagnosis Chart
by Symptom" .
5. Does the auto light system operate normally? If YES: GO TO 6. If NO: GO TO 4.
6. Inspection End.
Preliminary CheckEKS007AX
SETTING CHANGE FUNCTIONS

Sensitivity of auto light system can be adjusted using CONSULT-II. Refer to LT-58, "WORK SUPPORT" .
CHECK POWER SUPPLY AND GROUND CIRCUIT
1. CHECK FUSES OR FUSIBLE LINK
Check for blown fuses or fusible link.
Refer to LT- 5 0 , "
Wiring Diagram — AUTO/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" .
56L/W *1
Y *2Headlamp high (RH) ONLighting switch
HIGH or PASS
positionOFF 0V
ON Battery voltage
57 R/LParking, license, and tail
lampONLighting switch
1ST positionOFF 0V
ON Battery voltage
59 B Ground ON — 0V Terminal
No.Wire color Signal nameMeasuring condition
Reference value
(Approx.) Ignition
switchOperation or condition
Unit Power source Fuse No.
BCMBattery f
Ignition switch ON or START position 59
IPDM E/R Battery34
35
37
40
41
53

AUTO LIGHT SYSTEM
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Revision: August 20072004 QX56ACTIVE TEST
Operation Procedure
1. Touch “HEAD LAMP” on “SELECT TEST ITEM” screen.
2. Touch “ACTIVE TEST” on “SELECT DIAG MODE” screen.
3. Touch item to be tested and check operation of the selected item.
4. During the operation check, touching “BACK” deactivates the operation.
Display Item List
SELF-DIAGNOSTIC RESULTS
Operation Procedure
1. Touch “BCM” on “SELECT TEST ITEM” screen.
2. Touch “SELF-DIAG RESULTS” on “SELECT DIAG MODE” screen.
3. Self-diagnostic results are displayed.
HI BEAM SW “ON/OFF”Displays status (high beam switch: ON/Others: OFF) of high beam switch judged from
lighting switch signal.
HEAD LAMP SW 1 “ON/OFF”Displays status (headlamp switch 1: ON/Others: OFF) of headlamp switch 2 judged from
lighting switch signal.
HEAD LAMP SW 2 “ON/OFF”Displays status (headlamp switch 2: ON/Others: OFF) of headlamp switch 2 judged from
lighting switch signal.
LIGHT SW 1ST “ON/OFF”Displays status (lighting switch 1st position: ON/Others: OFF) of lighting switch judged
from lighting switch signal.
AUTO LIGHT SW “ON/OFF”Displays status of the lighting switch as judged from the lighting switch signal. (AUTO
position: ON/Other than AUTO position: OFF)
PASSING SW “ON/OFF”Displays status (flash-to-pass switch: ON/Others: OFF) of flash-to-pass switch judged
from lighting switch signal.
FR FOG SW “ON/OFF”Displays status (front fog lamp switch: ON/Others: OFF) of front fog lamp switch judged
from lighting switch signal.
DOOR SW-DR “ON/OFF”Displays status of the driver door as judged from the driver door switch signal. (Door is
open: ON/Door is closed: OFF)
DOOR SW-AS “ON/OFF”Displays status of the passenger door as judged from the passenger door switch signal.
(Door is open: ON/Door is closed: OFF)
DOOR SW-RR “ON/OFF”Displays status of the rear door as judged from the rear door switch (RH) signal. (Door is
open: ON/Door is closed: OFF)
DOOR SW-RL “ON/OFF”Displays status of the rear door as judged from the rear door switch (LH) signal. (Door is
open: ON/Door is closed: OFF)
BACK DOOR SW “ON/OFF”Displays status of the back door as judged from the back door latch (door ajar switch) sig-
nal. (Door is open: ON/Door is closed: OFF)
TURN SIGNAL R “ON/OFF” Displays status (Turn right: ON/Others: OFF) as judged from lighting switch signal.
TURN SIGNAL L “ON/OFF” Displays status (Turn left: ON/Others: OFF) as judged from lighting switch signal.
CARGO LAMP SW “ON/OFF” Displays status of cargo lamp.
OPTICAL SENSOR [0 - 5V] Displays “ambient light (close to 5V when dark/close to 0V when light)” judged from opti-
cal sensor signal. Monitor item Contents
Te s t i t e m D e s c r i p t i o n
TAIL LAMP Allows tail lamp relay to operate by switching ON-OFF.
HEAD LAMP Allows headlamp relay (HI, LO) to operate by switching ON-OFF.
FR FOG LAMP Allows fog lamp relay to operate by switching ON-OFF.
CARGO LAMP Allows cargo lamp to operate by switching ON-OFF.

AUTO LIGHT SYSTEM
LT-61
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Revision: August 20072004 QX56
4. Select the desired part to be diagnosed on the “SELECT DIAG
MODE” screen.
DATA MONITOR
Operation Procedure
1. Touch “DATA MONITOR” on “SELECT DIAG MODE ” screen.
2. Touch “ALL SIGNALS”, “MAIN SIGNALS” or “SELECTION FROM MENU” on the "SELECT MONITOR
ITEM" screen.
3. Touch “START”.
4. Touch the required monitoring item on “SELECTION FROM MENU”. In “ALL SIGNALS”, all items are
monitored. In “MAIN SIGNALS”, predetermined items are monitored.
5. Touch “RECORD” while monitoring to record the status of the item being monitored. To stop recording,
touch “STOP”.
All Items, Main Items, Select Item Menu
NOTE:
Perform monitoring of IPDM E/R data with the ignition switch ON. When the ignition switch is at ACC, the dis-
play may not be correct.
ACTIVE TEST
Operation Procedure
1. Touch “ACTIVE TEST” on “SELECT DIAG MODE” screen.
2. Touch item to be tested, and check operation.
3. Touch “START”.
4. Touch “STOP” while testing to stop the operation.
BCIA0031E
ALL SIGNALS All items will be monitored.
MAIN SIGNALS Monitor the predetermined item.
SELECTION FROM MENU Select any item for monitoring.
Item nameCONSULT-II
screen displayDisplay or
unitMonitor item selection
Description
ALL
SIGNALSMAIN
SIGNALSSELECTION
FROM MENU
Parking, license plate
and tail lamps requestTAIL&CLR REQ ON/OFF×× ×Signal status input from BCM
Headlamp low beam
requestHL LO REQ ON/OFF×× ×Signal status input from BCM
Headlamp high beam
requestHL HI REQ ON/OFF×× ×Signal status input from BCM
Front fog lamps request FR FOG REQ ON/OFF×× ×Signal status input from BCM
Test item CONSULT-II screen display Description
Tail lamp relay output TAIL LAMPAllows tail lamp relay to operate by switching operation ON-OFF at
your option.

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

HEADLAMP AIMING CONTROL
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HEADLAMP AIMING CONTROLPFP:26010
System DescriptionEKS007TL
The headlamp aiming system is controlled by the headlamp aiming switch.
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

to headlamp low relay, located in the IPDM E/R (intelligent power distribution module engine room).
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.
When the lighting switch is in the 2ND position or AUTO position (auto lights ON), the headlamp low relay
(located in the IPDM E/R) is energized. When energized, power is supplied

through 15A fuse (No. 41, located in the IPDM E/R)

through terminal 26 of the IPDM E/R

to terminal 8 of each front combination lamp (headlamp aiming motor).
Ground is supplied

to terminal 4 of each front combination lamp (headlamp aiming motor)

through grounds E9, E15 and E24, and

to terminal 7 of each front combination lamp (headlamp aiming motor)

through headlamp aiming switch and grounds M57, M61 and M79.
With power and ground supplied, headlamp aiming motors operate according to the aiming switch position.

LT-66
HEADLAMP AIMING CONTROL
Revision: August 20072004 QX56
Wiring Diagram — H/AIM —EKS007RW
WKWA3113E