2011 INFINITI QX56 CAN Communication Signal Chart

EXL-82
< DTC/CIRCUIT DIAGNOSIS >[XENON TYPE]
U1000 CAN COMM CIRCUIT
U1000 CAN COMM CIRCUIT
DescriptionINFOID:0000000006213948
CAN (Controller Area Network) is the serial transmissi
on for real time application. CAN is the multiplex com-
munication for the vehicle with superior data transmi ssion speed and error detection ability. Many electronic
control units are equipped on the vehicle. These control units do not operate individually, but associates with
other control units by sharing information. In CA N communication, each control unit is connected with two
communication lines (CAN-H and CAN-L). Much inform ation is transmitted with fewer communication lines
than before. Each control unit transmits/rec eives data and reads the necessary data only.
CAN Communication Signal Chart. Refer to LAN-27, "
CAN COMMUNICATION SYSTEM : CAN System Spec-
ification Chart".
DTC LogicINFOID:0000000006213949
DTC DETECTION LOGIC
Diagnosis ProcedureINFOID:0000000006213950
1.PERFORM SELF DIAGNOSTIC
1. Turn ignition switch ON and wait for 2 seconds or more.
2. Check “Self Diagnostic Result”.
Is
“CAN COMM CIRCUIT” displayed?
YES >> Refer to LAN-18, "Trouble Diagnosis Flow Chart".
NO >> Refer to GI-40, "
Intermittent Incident".
DTC No. Trouble diagnosis name DTC detection condition Possible causes
U1000 CAN communication circuit When AFS control unit does not trans-
mit/receive CAN communication signal
continuously for 2 seconds or more
CAN communication system
Revision: 2010 May2011 QX56

HAC-72
< DTC/CIRCUIT DIAGNOSIS >[AUTOMATIC AIR CONDITIONING]
U1000 CAN COMM CIRCUIT
DTC/CIRCUIT DIAGNOSIS
U1000 CAN COMM CIRCUIT
DescriptionINFOID:0000000006275903
CAN (Controller Area Network) is a serial communication
system for real time application. It is an on-vehicle
multiplex communication system with high data comm unication speed and excellent error detection ability.
Many electronic control units are equipped onto vehicl es, and each control unit shares information and links
with other control units during operation (not independent ). In CAN communication, control units are con-
nected with two communication lines (CAN-H line, CAN-L line) allowing a high rate of information transmission
with less wiring. Each control unit transmits/recei ves data but selectively reads required data only.
CAN Communication Signal Chart. Refer to LAN-28, "
CAN COMMUNICATION SYSTEM : CAN Communica-
tion Signal Chart".
DTC LogicINFOID:0000000006275904
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PERFORM SELF-DIAGNOSIS
With CONSULT-III
1. Turn ignition switch ON and wait for 2 seconds or more.
2. Select “Self Diagnostic Result” m ode of “HVAC” using CONSULT-.III
3. Check DTC.
Is DTC detected?
YES >> Refer to HAC-72, "Diagnosis Procedure".
NO >> Refer to GI-40, "
Intermittent Incident".
Diagnosis ProcedureINFOID:0000000006275905
1.CHECK CAN COMMUNICATION SYSTEM
Check CAN communication system. Refer to LAN-18, "
Trouble Diagnosis Flow Chart".
>> INSPECTION END
DTC Items
(CONSULT-III screen terms) DTC detection condition Possible cause
U1000 CAN COMM CIRCUIT When A/C auto amp. is not transmitting
or receiving CAN communication signal
for 2 or more seconds.
CAN communication system
Revision: 2010 May2011 QX56

HAC-142
< SYMPTOM DIAGNOSIS >[AUTOMATIC AIR CONDITIONING]
COMPRESSOR DOSE DOT OPERATE
COMPRESSOR DOSE DOT OPERATE
DescriptionINFOID:0000000006275994
Symptom: Compressor dose not operate.
Diagnosis ProcedureINFOID:0000000006275995
NOTE:
 Perform self-diagnoses with CONSULT-III before perfo
rming symptom diagnosis. If DTC is detected, per-
form the corresponding diagnosis.
 Check that refrigerant is enclosed in cooler cycle normally. If refrigerant amount is shortage from proper
amount, perform inspection of refrigerant leakage.
1.CHECK MAGNET CLUTCH OPERATION
Check magnet clutch. Refer to HAC-126, "
Component Function Check".
Does it operate normally?
YES >> GO TO 2.
NO >> Repair or replace malfunctioning parts.
2.CHECK REFRIGERANT PRESSURE SENSOR
Check refrigerant pressure sensor. Refer to EC-520, "
Component Function Check".
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace malfunctioning parts.
3.CHECK A/C AUTO AMP. OUTPUT SIGNAL
With CONSULT-III
Check “COMP REQ SIG” and “FAN REQ SIG” in “DAT A MONITOR” mode of “HVAC” using CONSULT-III.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Replace A/C auto amp.. Refer to HAC-146, "
Removal and Installation".
4.CHECK ECM INPUT SIGNAL
With CONSULT-III
Check “AIR COND SIG” and “HEATER FAN SW” in “D ATA MONITOR” mode of “ECM” using CONSULT-III.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Check CAN communication system. Refer to LAN-18, "
Trouble Diagnosis Flow Chart".
5.CHECK IPDM E/R INPUT SIGNAL
With CONSULT-III
1. Start engine.
Monitor item Condition Status
COMP REQ SIG A/C switch ON On
OFF Off
FAN REQ SIG Front blower motor ON On
OFF Off
Monitor item Condition Status
COMP REQ SIG A/C switch ON On
OFF Off
HEATER FAN SW Front blower motor ON On
OFF Off
Revision: 2010 May2011 QX56

LAN
LAN-1
ELECTRICAL & POWER CONTROL
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SECTION LAN
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CONTENTS
LAN SYSTEM
CAN FUNDAMENTAL
PRECAUTION ................ ...............................
7
PRECAUTIONS .............................................. .....7
Precautions for Trouble Diagnosis ...................... ......7
Precautions for Harness Repair ................................7
SYSTEM DESCRIPTION ..............................8
SYSTEM ......................................................... .....8
CAN COMMUNICATION SYSTEM .............................8
CAN COMMUNICATION SYSTEM : System De-
scription ............................................................... ......
8
CAN COMMUNICATION SYSTEM : System Dia-
gram ..........................................................................
8
CAN COMMUNICATION SYSTEM : CAN Com-
munication Control Circuit .........................................
9
DIAG ON CAN ....................................................... ......9
DIAG ON CAN : Description .....................................9
DIAG ON CAN : System Diagram ...........................10
TROUBLE DIAGNOSIS .....................................11
Condition of Error Detection ................................ ....11
Symptom When Error Occurs in CAN Communi-
cation System ...................................................... ....
11
CAN Diagnosis with CONSULT-III ..........................14
Self-Diagnosis .........................................................15
CAN Diagnostic Support Monitor ............................15
How to Use CAN Communication Signal Chart ......17
BASIC INSPECTION ...................................18
DIAGNOSIS AND REPAIR WORKFLOW ..... ....18
Trouble Diagnosis Flow Chart ............................. ....18
Trouble Diagnosis Procedure ..................................18
CAN
HOW TO USE THIS MANU AL .....................
23
HOW TO USE THIS SECTION ....................... ....23
Caution ................................................................ ....23
Abbreviation List ......................................................23
PRECAUTION ..............................................24
PRECAUTIONS .................................................24
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ....
24
Precautions for Trouble Diagnosis ..........................24
Precautions for Harness Repair ..............................24
SYSTEM DESCRIPTION .............................26
COMPONENT PARTS ......................................26
Component Parts Location .................................. ....26
SYSTEM ............................................................27
CAN COMMUNICATION SYSTEM ........................ ....27
CAN COMMUNICATION SYSTEM : CAN System
Specification Chart .............................................. ....
27
CAN COMMUNICATION SYSTEM : CAN Com-
munication Signal Chart ..........................................
28
WIRING DIAGRAM ......................................33
CAN SYSTEM (WITH ICC) ...............................33
Wiring Diagram .................................................... ....33
CAN SYSTEM (WITHOUT ICC) ........................46
Wiring Diagram ........................................................46
BASIC INSPECTION ...................................56
DIAGNOSIS AND REPAIR WORKFLOW ........56
Interview Sheet .................................................... ....56
DTC/CIRCUIT DIAGNOSIS .........................57
MALFUNCTION AREA CHART ........................57
System Diagram .................................................. ....57
CAN Communication Circuit ....................................57
Revision: 2010 May2011 QX56

LAN
TROUBLE DIAGNOSISLAN-17
< SYSTEM DESCRIPTION > [CAN FUNDAMENTAL]
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How to Use CAN Communication Signal ChartINFOID:0000000006220522
The CAN communication signal chart lists the signals
needed for trouble diagnosis. It is useful for detecting
the root cause by finding a signal related to the sy mptom, and by checking transmission and reception unit.
SKIB8715E
Revision: 2010 May2011 QX56

LAN-28
< SYSTEM DESCRIPTION >[CAN]
SYSTEM
Check CAN system type from the vehicle shape and equipment.
CAN COMMUNICATION SYSTEM : CA
N Communication Signal ChartINFOID:0000000006220533
Refer to LAN-17, "How to Use CAN Communication Signal Chart" for how to use CAN communication signal
chart.
T: Transmit R: Receive
1. ICC sensor
A. With ICC system
JSMIA0342ZZ
Signal nameECM
4WD
ABS
TCM
A-BAG
AFSAV
BCM
CGW
HVAC
M&A
STRG
TPMS
IPDM-E ADP
PSB
E-SUS ICC
PWBD
A/C compressor request
signal TR
Accelerator pedal position
signal TRRR
R
ASCD OD cancel request
signal TR
ASCD operation signal T R
ASCD status signal T R
Closed throttle position sig-
nal TR
R
Cooling fan speed request
signal TR
Engine and A/T integrated
control signal TR
RT
Engine coolant temperature
signal TRR
Engine restart request sig-
nal TRR
TR
Engine speed signal T R R R R R R R
Engine status signal T R R R
Engine torque signal T R
Fuel consumption monitor
signal TRR
ICC brake switch signal T R
ICC prohibition signal T R
ICC steering switch signal T R
Malfunctioning indicator
lamp signal TR
N idle instruction signal TR
RT
Revision: 2010 May2011 QX56

LAN
U1000 CAN COMM CIRCUITLAN-113
< DTC/CIRCUIT DIAGNOSIS > [CAN GATEWAY]
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DTC/CIRCUIT DIAGNOSIS
U1000 CAN COMM CIRCUIT
DescriptionINFOID:0000000006220585
CAN (Controller Area Network) is a serial communication line for real time applications. It is an on-vehicle mul-
tiplex communication line with high data communicati
on speed and excellent error detection ability. Modern
vehicle is equipped with many electroni c control unit, and each control unit shares information and links with
other control units during operation (not independent). In CAN communication, control units are connected
with two communication lines (CAN-H and CAN-L) allowing a high rate of information transmission with less
wiring. Each control unit transmits/receives data but selectively reads required data only.
CAN Communication Signal Chart. Refer to LAN-28, "
CAN COMMUNICATION SYSTEM : CAN Communica-
tion Signal Chart".
DTC LogicINFOID:0000000006220586
DTC DETECTION LOGIC
Diagnosis ProcedureINFOID:0000000006220587
1.PERFORM SELF DIAGNOSTIC
1. Turn the ignition switch ON and wait for 2 seconds or more.
2. Check “Self Diagnostic Result”.
Is
“U1000: CAN COMM CIRCUIT” displayed?
YES >> Refer to LAN-18, "Trouble Diagnosis Flow Chart".
NO >> Refer to GI-40, "
Intermittent Incident".
DTCCONSULT-III display de-
scription DTC Detection
Condition Possible cause
U1000 CAN COMM CIRCUIT When CAN gateway cannot communicate
CAN communication signal continuously for 2
seconds or more.
CAN communication system
Revision: 2010 May2011 QX56

LAN-114
< DTC/CIRCUIT DIAGNOSIS >[CAN GATEWAY]
U1010 CONTROL UNIT (CAN)
U1010 CONTROL UNIT (CAN)
DescriptionINFOID:0000000006220588
CAN (Controller Area Network) is a serial communication
line for real time applications. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Modern
vehicle is equipped with many electronic control unit, and each control unit shares information and links with
other control units during operation (not independent). In CAN communication, control units are connected
with two communication lines (CAN-H and CAN-L) allo wing a high rate of information transmission with less
wiring. Each control unit transmits/receives data but selectively reads required data only.
CAN Communication Signal Chart. Refer to LAN-28, "
CAN COMMUNICATION SYSTEM : CAN Communica-
tion Signal Chart".
DTC LogicINFOID:0000000006220589
DTC DETECTION LOGIC
Diagnosis ProcedureINFOID:0000000006220590
1.REPLACE CAN GATEWAY
When DTC “U1010: CONTROL UNIT(CAN)” is detected, replace CAN gateway.
>> Replace CAN gateway. Refer to LAN-117, "
Removal and Installation".
DTCCONSULT-III display
description DTC Detection
Condition Possible cause
U1010 CONTROL UNIT(CAN) When an error is detected during the initial di-
agnosis for CAN contro
ller of CAN gateway. CAN gateway
Revision: 2010 May2011 QX56