LAN
TROUBLE DIAGNOSISLAN-9
< FUNCTION DIAGNOSIS > [CAN FUNDAMENTAL]
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Example: Main Line Between Data Link Connector and ABS Actuator and Electr
ic Unit (Control Unit) Open Circuit
Example: CAN-H, CAN-L Harness Short Circuit
SKIB8740E
Unit name Symptom
ECM Engine torque limiting is affected, and shift harshness increases.
BCM • Reverse warning chime does not sound.
• The front wiper moves under continuous operation mode even though the front wip-
er switch being in the intermittent position.
EPS control unit The steering effort increases.
Combination meter • The shift position indicator and OD OFF indicator turn OFF.
• The speedometer is inoperative.
• The odo/trip meter stops.
ABS actuator and electric unit (control unit) Normal operation.
TCM No impact on operation.
IPDM E/R When the ignition switch is ON,
• The headlamps (Lo) turn ON.
• The cooling fan continues to rotate.
SKIB8741E
Revision: December 20092009 QX56
LAN-10
< FUNCTION DIAGNOSIS >[CAN FUNDAMENTAL]
TROUBLE DIAGNOSIS
Self-Diagnosis
INFOID:0000000003776437
CAN Diagnostic Support MonitorINFOID:0000000003776438
CONSULT-III and CAN diagnostic support monitor (on-boar d diagnosis function) are used for detecting root
cause.
MONITOR ITEM (CONSULT-III)
Unit name Symptom
ECM • Engine torque limiting is affected, and shift harshness increases.
• Engine speed drops.
BCM • Reverse warning chime does not sound.
• The front wiper moves under continuous operation mode even though the front
wiper switch being in the intermittent position.
• The room lamp does not turn ON.
• The engine does not start (if an error or malfunction occurs while turning the igni- tion switch OFF.)
• The steering lock does not release (if an error or malfunction occurs while turning the ignition switch OFF.)
EPS control unit The steering effort increases.
Combination meter • The tachometer and the speedometer do not move.
• Warning lamps turn ON.
• Indicator lamps do not turn ON.
ABS actuator and electric unit (control unit) Normal operation.
TCM No impact on operation.
IPDM E/R When the ignition switch is ON,
• The headlamps (Lo) turn ON.
• The cooling fan continues to rotate.
DTC
Self-diagnosis item
(CONSULT-III indication) DTC detection condition
Inspection/Action
U1000 CAN COMM CIRCUIT When ECM is not transmitting or receiving CAN
communication signal of OBD (emission-related
diagnosis) for 2 seconds or more.
Refer to LAN-13
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When a control unit (except for ECM) is not
transmitting or receiving CAN communication
signal for 2 seconds or more.
U1001 CAN COMM CIRCUIT When ECM is not transmitting or receiving CAN
communication signal other than OBD (emis-
sion-related diagnosis) for 2 seconds or more.
U1002 SYSTEM COMM When a control unit is not transmitting or receiv-
ing CAN communication signal for 2 seconds or
less. Start the inspection. Re-
fer to the applicable sec-
tion of the indicated
control unit.
U1010 CONTROL UNIT(CAN) When an error is detected during the initial diag-
nosis for CAN controller of each control unit. Replace the control unit
indicating “U1010”.
Revision: December 20092009 QX56
LAN
DIAGNOSIS AND REPAIR WORKFLOWLAN-31
< BASIC INSPECTION > [CAN FUNDAMENTAL]
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b. Reception item of “ABS”: Assume that the unit
could not receive the signal from ECM. Draw a line
between ABS and ECM (line 3-b in the figure below).
4. Search for the possible cause using CAN communication signal chart using information from the interview with the customer.
NOTE:
For the details of CAN communication signal, refer to LAN-44, "
CAN Communication Signal Chart".
a. ABS warning lamp turned ON and speedometer did not move: This means that “ABS warning lamp signal”
and “Vehicle speed signal” could not communicate between M&A and ABS (4-a in the figure below).
PKID1223E
Revision: December 20092009 QX56
LAN-32
< BASIC INSPECTION >[CAN FUNDAMENTAL]
DIAGNOSIS AND REPAIR WORKFLOW
b. The tachometer moved normally: This means that “Engine speed signal” could communicate normally
between ECM and M&A (4-b in the figure below).
5. Fill out the diagnosis sheet based on information from step 4.
a. The ABS warning lamp turned ON and speedometer did not move: Assume that a possible cause is no communication between M&A and ABS. Draw a line between M&A and ABS. (Line 5-a in the figure
below).
SKIB8895E
Revision: December 20092009 QX56
LAN
PRECAUTIONSLAN-37
< PRECAUTION > [CAN]
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PRECAUTION
PRECAUTIONS
Precaution for Supplemental
Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000003776445
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 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 “SRS AIR BAG” and “SEAT BELT” of this
Service Manual.
WARNING:
• To avoid rendering the SRS inoper ative, 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 in correct removal and installation of the SRS, can lead to personal
injury caused by unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the “SRS AIR BAG”.
• Do not use electrical test equipm ent 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 Air Bag Diagnosis Sensor Unit or other Air Bag System sensors with the
ignition ON or engine running, DO NOT use air or electric 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 minutes before performing any service.
Precautions for Trouble DiagnosisINFOID:0000000003776446
CAUTION:
• Never apply 7.0 V or more to the measurement terminal.
• Use a tester with open terminal voltage of 7.0 V or less.
• Turn the ignition switch OFF and disconnect th e battery cable from the negative terminal when
checking the harness.
Precautions for Harness RepairINFOID:0000000003776447
• Solder the repaired area and wrap tape around the soldered area.
NOTE:
A fray of twisted lines must be within 110 mm (4.33 in).
SKIB8766E
Revision: December 20092009 QX56
LAN
CAN COMMUNICATION SYSTEMLAN-45
< FUNCTION DIAGNOSIS > [CAN]
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Engine speed signal
T RRR R R R R R
Engine status signal TR
Fuel consumption monitor signal TR
RT
ICC steering switch signal TR
Malfunction indicator lamp signal T R
Wide open throttle position signal T R
A/T CHECK indicato r lamp signal T R
A/T fluid temperature sensor signal T R
A/T position indicator lamp signal TR RR
A/T self-diagnosis signal R T
Current gear position signal TR R
Input speed signal R TR
Output shaft revolution signal R TR R
P range signal TR R RR
ICC sensor signal T R
Buzzer output signal TR
TR
ICC OD cancel request signal R RT
ICC operation signal R RT
ICC system display signal TR
System setting signal TRT
RTR
A/C switch/indicator signal TR
RT
A/C switch signal RT R
Blower fan motor switch signal RT
Day time running light request signal TR R
Door lock/unlock status signal TR
Door switch signal R R TR R R
Front fog light request signal TR
Front wiper request signal RT R
High beam request signal TR R
Horn chirp signal TR
Ignition switch signal RTR R
Key fob door unlock signal RT
Key fob ID signal RT
Key switch signal RT
Low beam request signal TR
Position light request signal TR R
Rear window defogger switch signal T RR
Sleep wake up signal RT R R
Theft warning horn request signal TR
Signal name/Connecting unit
ECM
TCM
LASER ICC
ADP AV
BCM
HVAC I-KEY M&A
STRG 4WD
ABS
IPDM-E
Revision: December 20092009 QX56
LAN-46
< FUNCTION DIAGNOSIS >[CAN]
CAN COMMUNICATION SYSTEM
NOTE:
CAN data of the air bag diagnosis sensor unit is not us
ed by usual service work, thus it is omitted.
Tire pressure data signal R T
Tire pressure signal R TR
Turn indicator signal TR
Buzzer output signal TR
Door lock/unlock request signal RT
Hazard request signal RT
Hazard warning lamp request signal RT
Ignition knob switch signal RT
KEY warning signal TR
LOCK warning signal TR
Panic alarm request signal RT
Power window open request signal RT
1st position switch signal R T
4th position switch signal R T
Distance to empty signal RT
Fuel level low warning signal RT
Fuel level sensor signal R T
Parking brake switch signal RT
Seat belt buckle switch signal RT
Stop lamp switch signal R T
Tow mode switch signal R T
Vehicle speed signal RRR RRR R T
RRRT
Steering angle sensor signal TR
ABS malfunction signal RT
ABS warning lamp signal RT
Brake pressure sensor signal RT
Brake warning lamp signal RT
SLIP indicator lamp signal RT
TCS malfunction signal RT
VDC malfunction signal RT
VDC OFF indicator lamp signal RRT
VDC operation signal RT
Front wiper stop position signal RT
High beam status signal R T
Hood switch signal RT
Low beam status signal R T
Rear window defogger control signal R RT
Signal name/Connecting unit
ECM
TCM
LASER ICC
ADP
AV
BCM
HVAC I-KEY M&A
STRG 4WDABS
IPDM-E
Revision: December 20092009 QX56
LU-2
< PRECAUTION >
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000005851889
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 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 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 NISSAN/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 harn esses can be identified 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.
Precaution Necessary for Steering W heel Rotation After Battery Disconnect
INFOID:0000000005851890
NOTE:
• This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
• Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK ″ position.
• Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS, an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be rotated.
4. Perform the necessary repair operation.
Revision: December 20092009 QX56