EC-56
< FUNCTION DIAGNOSIS >[VK56DE]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
When there is an open circuit on MIL circuit, the ECM c
annot warn the driver by lighting up MIL when there is
malfunction on engine control system.
Therefore, when electrical controlled throttle and part of ECM related diagnoses are continuously detected as
NG for 5 trips, ECM warns the driver that engine cont rol system malfunctions and MIL circuit is open by means
of operating fail-safe function.
The fail-safe function also operates when above diagnos es except MIL circuit are detected and demands the
driver to repair the malfunction.
MIL Flashing Without DTC
When any SRT codes are not set, MIL may fl ash without DTC. For the details, refer to EC-456, "DTC Index".
HOW TO SWITCH DIAGNOSTIC TEST MODE
NOTE:
It is better to count the ti me accurately with a clock.
It is impossible to switch the di agnostic mode when an accelerator pedal position sensor circuit has
a malfunction.
Always ECM returns to Diagnostic Test Mode I after ignition switch is turned OFF.
How to Set Diagnostic Test Mode II (Self-diagnostic Results)
1. Confirm that accelerator pedal is fully released, turn ignition switch ON and wait 3 seconds.
2. Repeat the following procedure quickly five times within 5 seconds.
a. Fully depress the accelerator pedal.
b. Fully release the accelerator pedal.
3. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 10 seconds until the MIL starts
blinking.
NOTE:
Do not release the accelerator pedal for 10 seconds if MIL may start blinking on the halfway of this
10 seconds. This blinking is displaying SRT status and is continued for another 10 seconds. For
the details, refer to EC-456, "DTC Index"
.
Diagnostic Test
ModeKEY and ENG.
Status Function Explanation of Function
Mode I Ignition switch in ON position
Engine stopped BULB CHECK This function checks the MIL bulb for damage (blown, open
circuit, etc.).
If the MIL does not come on, check MIL circuit.
Engine running MALFUNCTION WARNING This is a usual driving condition. When a malfunction is de-
tected twice in two consecutive driving cycles (two trip de-
tection logic), the MIL will light up to inform the driver that a
malfunction has been detected.
The following malfunctions will light up or blink the MIL in
the 1st trip.
Misfire (Possible three way catalyst damage)
One trip detection diagnoses
Mode II Ignition switch in ON position
Engine stopped SELF-DIAGNOSTIC
RESULTS
This function allows DTCs an
d 1st trip DTCs to be read.
Engine operating condition in fail-safe mode Engine speed will not rise more than 2,500 rpm due to the fuel cut
Revision: December 20092009 QX56
EC-480
< PRECAUTION >[VK56DE]
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint S
ystem (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000005867525
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty 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 w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
To avoid rendering the SRS inopera tive, 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 NISS AN/INFINITI dealer.
Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the SR section.
Do not use electrical test equipmen t on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
When working near the Airbag Diagnosis Sensor Unit or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or electri c power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minu tes before performing any service.
On Board Diagnosis (OBD) System of Engine and A/TINFOID:0000000003771742
The ECM has an on board diagnostic system. It will light up the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:
Be sure to turn the ignition sw itch OFF and disconnect the negative battery cable before any repair
or inspection work. The open/short circuit of re lated switches, sensors, solenoid valves, etc. will
cause the MIL to light up.
Be sure to connect and lock the connectors secure ly after work. A loose (unlocked) connector will
cause the MIL to light up due to the open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
Certain systems and components, especially those related to OBD, may use a new style slide-lock-
ing type harness connector. For descrip tion and how to disconnect, refer to PG-68
.
Be sure to route and secure the harnesses properly after work. The interference of the harness with
a bracket, etc. may cause the MIL to li ght up due to the short circuit.
Be sure to connect rubber tubes properly afte r work. A misconnected or disconnected rubber tube
may cause the MIL to light up due to the malfunction of the EVAP system or fuel injection system,
etc.
Be sure to erase the unnecessary malfunction info rmation (repairs completed) from the ECM and
TCM (Transmission control module) before returning the vehicle to the customer.
Revision: December 20092009 QX56
EXL-1
DRIVER CONTROLS
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SECTION EXL
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CONTENTS
EXTERIOR LIGHTING SYSTEM
BASIC INSPECTION ....... .............................4
DIAGNOSIS AND REPAIR WORKFLOW ..... .....4
Work Flow ........................................................... ......4
FUNCTION DIAGNOSIS ...............................7
HEADLAMP .................................................... .....7
System Diagram .................................................. ......7
System Description ...................................................7
Component Parts Location ........................................7
Component Description .............................................7
DAYTIME LIGHT SYSTEM .................................9
System Diagram .................................................. ......9
System Description ...................................................9
Component Parts Location ........................................9
Component Description ...........................................10
AUTO LIGHT SYSTEM ......................................11
System Diagram ......................................................11
System Description .................................................11
Component Parts Location ......................................12
Component Description ...........................................12
HEADLAMP AIMING SYSTEM (MANUAL) .......13
System Diagram .................................................. ....13
System Description .................................................13
Component Parts Location ......................................13
Component Description ...........................................13
FRONT FOG LAMP ............................................14
System Diagram .................................................. ....14
System Description .................................................14
Component Parts Location ......................................14
Component Description ...........................................14
TURN SIGNAL AND HAZARD WARNING
LAMPS ...............................................................
15
System Diagram .................................................. ....15
System Description .................................................15
Component Parts Location ......................................15
Component Description ....................................... ....16
PARKING, LICENSE PLATE AND TAIL
LAMPS ..............................................................
17
System Diagram ......................................................17
System Description ..................................................17
Component Parts Location ......................................17
Component Description ...........................................18
TRAILER TOW ..................................................19
System Diagram ......................................................19
System Description ..................................................19
Component Parts Location ......................................20
Component Description ...........................................20
DIAGNOSIS SYSTEM (BCM) ...........................22
HEADLAMP ........................................................... ....22
HEADLAMP : CONSULT-III Function (BCM -
HEAD LAMP) ...........................................................
22
FLASHER ............................................................... ....23
FLASHER : CONSULT-III Function (BCM -
FLASHER) ...............................................................
23
COMB SW .............................................................. ....23
COMB SW : CONSULT-III Function (BCM -
COMB SW) ..............................................................
23
DIAGNOSIS SYSTEM (IPDM E/R) ...................25
Diagnosis Description ..............................................25
CONSULT - III Function (IPDM E/R) .......................27
COMPONENT DIAGNOSIS .........................30
POWER SUPPLY AND GROUND CIRCUIT ....30
BCM (BODY CONTROL MODULE) ...................... ....30
BCM (BODY CONTROL MODULE) : Diagnosis
Procedure ............................................................ ....
30
IPDM E/R (INTELLIGENT POWER DISTRIBU-
TION MODULE ENGINE ROOM) .......................... ....
31
Revision: December 20092009 QX56
EXL-2
IPDM E/R (INTELLIGENT POWER DISTRIBU-
TION MODULE ENGINE ROOM) : Diagnosis Pro-
cedure .....................................................................
31
HEADLAMP (HI) CIRCUIT ................................32
Description ........................................................... ...32
Component Function Check ...................................32
Diagnosis Procedure - Without Daytime Light Sys-
tem ..........................................................................
32
Diagnosis Procedure - With Daytime Light System
...
33
HEADLAMP (LO) CIRCUIT ...............................35
Description ........................................................... ...35
Component Function Check ...................................35
Diagnosis Procedure - Without Daytime Light Sys-
tem ..........................................................................
35
Diagnosis Procedure - With Daytime Light System
...
36
FRONT FOG LAMP CIRCUIT ...........................38
Description ........................................................... ...38
Component Function Check ...................................38
Diagnosis Procedure ..............................................38
PARKING LAMP CIRCUIT ................................40
Description ........................................................... ...40
Component Function Check ...................................40
Diagnosis Procedure - Without Daytime Light Sys-
tem ..........................................................................
40
Diagnosis Procedure - With Daytime Light System
...
42
TURN SIGNAL LAMP CIRCUIT ........................46
Description ........................................................... ...46
Component Function Check ...................................46
Diagnosis Procedure ..............................................46
OPTICAL SENSOR ...........................................49
Description ..............................................................49
Component Function Check ...................................49
Diagnosis Procedure ..............................................49
HEADLAMP AIMING SWITCH ..........................51
Description ........................................................... ...51
Diagnosis Procedure - Without Daytime Light Sys-
tem ..........................................................................
51
Diagnosis Procedure - With Daytime Light System
...
52
HEADLAMP .......................................................53
Wiring Diagram .................................................... ...53
DAYTIME LIGHT SYSTEM ................................57
Wiring Diagram .................................................... ...57
AUTO LIGHT SYSTEM ......................................64
Wiring Diagram .................................................... ...64
HEADLAMP AIMING SYSTEM (MANUAL) ......71
Wiring Diagram .................................................... ...71
FRONT FOG LAMP SYSTEM ...........................75
Wiring Diagram .................................................... ...75
TURN SIGNAL AND HAZARD WARNING
LAMP SYSTEM .............................................. ...
78
Wiring Diagram .................................................... ...78
PARKING, LICENSE PLATE AND TAIL
LAMPS SYSTEM ...............................................
85
Wiring Diagram .................................................... ...85
STOP LAMP ......................................................91
Wiring Diagram .................................................... ...91
BACK-UP LAMP ............................................ ...95
Wiring Diagram .................................................... ...95
TRAILER TOW .................................................100
Wiring Diagram .....................................................100
ECU DIAGNOSIS ......................................106
BCM (BODY CONTROL MODULE) ............... ..106
Reference Value .................................................. .106
Terminal Layout ....................................................108
Physical Values .....................................................108
Wiring Diagram .....................................................114
Fail Safe ...............................................................118
DTC Inspection Priority Chart .............................119
DTC Index ............................................................119
IPDM E/R (INTELLIGENT POWER DISTRI-
BUTION MODULE ENGINE ROOM) ................
121
Reference Value .................................................. .121
Terminal Layout ....................................................123
Physical Values .....................................................123
Wiring Diagram .....................................................128
Fail Safe ...............................................................131
DTC Index ............................................................133
SYMPTOM DIAGNOSIS ...........................134
EXTERIOR LIGHTING SYSTEM SYMPTOMS ..134
Symptom Table .................................................... .134
NORMAL OPERATING CONDITION ...............136
Description ........................................................... .136
BOTH SIDE HEADLAMPS DO NOT SWITCH
TO HIGH BEAM ................................................
137
Description ........................................................... .137
Diagnosis Procedure .............................................137
BOTH SIDE HEADLAMPS (LO) ARE NOT
TURNED ON .....................................................
138
Description ............................................................138
Diagnosis Procedure .............................................138
PARKING, LICENSE PLATE AND TAIL
LAMPS ARE NOT TURNED ON ......................
139
Description ........................................................... .139
Revision: December 20092009 QX56
EXL-16
< FUNCTION DIAGNOSIS >
TURN SIGNAL AND HAZARD WARNING LAMPS
Component Description
INFOID:0000000003776166
1. Combination meter M23, M24 2. Combination switch M28 3. Hazard switch M55
4. BCM M18, M20 (view with instrument panel removed)
Part name Description
BCM Controls turn signal and hazard flasher operation.
Combination switch Lighting and turn signal switch requests are output to the BCM.
Hazard switch Hazard flasher request signal is output to the BCM.
Combination meter Outputs turn and hazard indicator as requested by the BCM.
Revision: December 20092009 QX56
EXL-28
< FUNCTION DIAGNOSIS >
DIAGNOSIS SYSTEM (IPDM E/R)
ACTIVE TEST
Te s t i t e m
Monitor Item[Unit] MAIN SIG-
NALS Description
MOTOR FAN REQ
[1/2/3/4] ×Displays the status of the cooling fan speed request signal received from ECM via
CAN communication.
A/C COMP REQ
[OFF/ON] ×Displays the status of the A/C request signal received from AV control unit via
CAN communication.
TA I L & C L R R E Q
[OFF/ON] ×
Displays the status of the position light request signal received from BCM via CAN
communication.
HL LO REQ
[OFF/ON] ×Displays the status of the low beam request signal received from BCM via CAN
communication.
HL HI REQ
[OFF/ON] ×Displays the status of the high beam request signal received from BCM via CAN
communication.
FR FOG REQ
[OFF/ON] ×
Displays the status of the front fog lamp request signal received from BCM via
CAN communication.
HL WASHER REQ
[OFF/ON] NOTE:
This item is displayed, but cannot be monitored.
FR WIP REQ
[STOP/1LOW/LOW/HI] ×Displays the status of the front wiper request signal received from BCM via CAN
communication.
WIP AUTO STOP
[STOP P/ACT P] ×
Displays the status of the front wiper auto stop signal judged by IPDM E/R.
WIP PROT
[OFF/Block] ×
Displays the status of the front wiper fail-safe operation judged by IPDM E/R.
ST RLY REQ
[OFF/ON] Displays the status of the starter request signal received from ECM via CAN com-
munication.
IGN RLY
[OFF/ON] ×
Displays the status of the ignition relay judged by IPDM E/R.
RR DEF REQ
[OFF/ON] ×Displays the status of the rear defogger request signal received from AV control
unit via CAN communication.
OIL P SW
[OPEN/CLOSE] Displays the status of the oil pressure switch judged by IPDM E/R.
DTRL REQ
[OFF] Displays the status of the daytime light request signal received from BCM via CAN
communication.
HOOD SW
[OPEN/CLOSE] Displays the status of the hood switch judged by IPDM E/R.
THFT HRN REQ
[OFF/ON] Displays the status of the theft warning horn request signal received from BCM
via CAN communication.
HORN CHIRP
[OFF/ON] Displays the status of the horn reminder signal received from BCM via CAN com-
munication.
Test item
Operation Description
REAR DEFOGGER OFF
OFF
ON Operates rear window defogger relay.
FRONT WIPER OFF
OFF
LO Operates the front wiper relay.
HI Operates the front wiper relay and front wiper high relay.
MOTOR FAN 1O
FF
2O FF
3 Operates the cooling fan relay.
4 Operates the cooling fan relay.
Revision: December 20092009 QX56
BCM (BODY CONTROL MODULE)EXL-109
< ECU DIAGNOSIS >
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color Signal name Signal
input/
output Measuring condition
Reference value or waveform
(Approx.)
Ignition
switch Operation or condition
1BR/W Ignition keyhole illumi-
nation Output OFFDoor is locked (SW OFF)
Battery voltage
Door is unlocked (SW ON) 0V
2SB Combination switch
input 5 Input ON
Lighting, turn, wiper OFF
Wiper dial position 4
3G/Y Combination switch
input 4 Input ONLighting, turn, wiper OFF
Wiper dial position 4
4Y Combination switch
input 3 Input ON
Lighting, turn, wiper OFF
Wiper dial position 4
5G/B Combination switch
input 2
Input ONLighting, turn, wiper OFF
Wiper dial position 4
6V Combination switch
input 1
9GR/R Rear window defogger
switch
Input ONRear window defogger switch
ON
0V
Rear window defogger switch
OFF 5V
10 G Hazard lamp flash Input OFF ON (opening or closing)
0V
OFF (other than above) Battery voltage
11 O Ignition switch (ACC
or ON)
InputACC or
ON Ignition switch ACC or ON
Battery voltage
12 R/L Front door switch RH Input OFF ON (open)
0V
OFF (closed) Battery voltage
13 GR Rear door switch RH Input OFF ON (open)
0V
OFF (closed) Battery voltage
15 L/W Tire pressure warning
check connector
Input OFF
—5V
18 P Remote keyless entry
receiver and optical
sensor (ground)
Output OFF
—0V
SKIA5291E
SKIA5292E
SKIA5291E
SKIA5292E
Revision: December 20092009 QX56
INL-58
< ECU DIAGNOSIS >
BCM (BODY CONTROL MODULE)
Te r m i n a lWire
color Signal name Signal
input/
output Measuring condition
Reference value or waveform
(Approx.)
Ignition
switch Operation or condition
1BR/W Ignition keyhole illumi-
nation Output OFFDoor is locked (SW OFF)
Battery voltage
Door is unlocked (SW ON) 0V
2SB Combination switch
input 5 Input ON
Lighting, turn, wiper OFF
Wiper dial position 4
3G/Y Combination switch
input 4 Input ONLighting, turn, wiper OFF
Wiper dial position 4
4Y Combination switch
input 3 Input ON
Lighting, turn, wiper OFF
Wiper dial position 4
5G/B Combination switch
input 2
Input ONLighting, turn, wiper OFF
Wiper dial position 4
6V Combination switch
input 1
9GR/R Rear window defogger
switch
Input ONRear window defogger switch
ON
0V
Rear window defogger switch
OFF 5V
10 G Hazard lamp flash Input OFF ON (opening or closing)
0V
OFF (other than above) Battery voltage
11 O Ignition switch (ACC
or ON)
InputACC or
ON Ignition switch ACC or ON
Battery voltage
12 R/L Front door switch RH Input OFF ON (open)
0V
OFF (closed) Battery voltage
13 GR Rear door switch RH Input OFF ON (open)
0V
OFF (closed) Battery voltage
15 L/W Tire pressure warning
check connector
Input OFF
—5V
18 P Remote keyless entry
receiver and optical
sensor (ground)
Output OFF
—0V
SKIA5291E
SKIA5292E
SKIA5291E
SKIA5292E
Revision: December 20092009 QX56