2011 INFINITI QX56 ECU

MWI-40
< ECU DIAGNOSIS INFORMATION >
COMBINATION METER
11
(G) Ground Enter switch signal Input Ignition
switch
ONWhen switch (enter
switch) is pressed
0 V
Other than the above 5 V
12
(O) Ground Select switch signal Input Ignition
switch
ONWhen switch (select
switch) is pressed
0 V
Other than the above 5 V
13
(W/R) Ground
Illumination control switch
signal (+) InputIgnition
switch
ON When switch [illumi-
nation control sw
itch (+)] is
pressed 0 V
Other than the above 5 V
14
(R) Ground Illumination control switch
signal (
−) InputIgnition
switch
ON When switch [illumi-
nation control switch (
−)] is
pressed 0 V
Other than the above 5 V
15
(R/W) Ground Air bag signal Input Ignition
switch
ONAir bag warning lamp
ON
4 V
Air bag warning lamp
OFF 0 V
18
(W/R) Ground Ambient sensor signal Input — —
19
(V/W) Ground A/C auto amp. connection
recognition signal Input —When A/C auto amp. is
connected
5 V
Other than the above 0 V
20
(B) Ground Ambient sensor ground — Ignition
switch
ON—0 V
21
(L) —CAN-H — — — —
22
(P) —CAN-L — — — —
23
(B) Ground Ground — Ignition
switch
ON
—0 V
24
(V) Ground Fuel level sensor ground — Ignition
switch
ON—0 V
25
(O/L) Ground Alternator signal Input Ignition
switch
ONCharge warning lamp ON 2 V
Charge warning lamp OFF Battery voltage
26
(W) Ground Parking brake switch signal Input Ignition
switch
ONParking brake applied 0 V
Parking brake released 12 V
Te r m i n a l N o .
(Wire color) Description
ConditionVa l u e
(Approx.)
+ – Signal name Input/
Output
JSNIA0014GB
Revision: 2010 May2011 QX56

MWI
COMBINATION METERMWI-41
< ECU DIAGNOSIS INFORMATION >
C
DE
F
G H
I
J
K L
M B A
O P
28
(GR/R) Ground Security signal Input Ignition
switch
ONSecurity indicator lamp ON 0 V
Security indicator lamp
OFF
12 V
29
(BR) Ground Washer level switch signal Input Ignition
switch
ONWasher level switch ON 0 V
Washer level switch OFF 5 V
30
(SB) Ground
Vehicle speed signal
(2-pulse) OutputIgnition
switch
ON Speedometer operated
[When vehicle speed is ap-
prox. 40 km/h (25 MPH)] NOTE:
The maximum voltage varies de-
pending on the specification
(destination unit).
31
(BR/W) GroundVehicle speed signal
(8-pulse)
OutputIgnition
switch
ONSpeedometer operated
[When vehicle speed is ap-
prox. 40 km/h (25 MPH)] NOTE:
The maximum voltage varies de-
pending on the specification
(destination unit).
33
(W) Ground SNOW mode signal Input Ignition
switch
ONWhen SNOW mode switch
is pressed
12 V
Other than the above 0 V
34
(BR/Y) Ground Fuel level sensor signal Input Ignition
switch
ON
—
35
(O/B) Ground Seat belt buckle switch sig-
nal (driver side)
InputIgnition
switch
ON When driver side belts is
fastened
12 V
When driver side belts is
unfastened 0 V
36
(G/Y) Ground Passenger seat belt warn-
ing signal
InputIgnition
switch
ON  When driver side seat
belt fastened
 When getting in the pas- senger seat
 When passenger seat belt fastened 12 V
 When driver side seat belt fastened
 When getting in the pas- senger seat
 When passenger seat belt unfastened 0 V
Te r m i n a l N o .
(Wire color) Description
ConditionVa l u e
(Approx.)
+ – Signal name Input/
Output
JSNIA0015GB
JSNIA0012GB
JSNIA3013ZZ
Revision: 2010 May2011 QX56

MWI-42
< ECU DIAGNOSIS INFORMATION >
COMBINATION METER
Fail-Safe
INFOID:0000000006221722
FA I L - S A F E
The combination meter activates the fail-safe contro l if CAN communication with each unit is malfunctioning.
37
(R/Y) Ground Non-manual mode signal Input Ignition
switch
ONSelector manual mode po-
sition
12 V
Other than the above 0 V
38
(L/W) Ground Manual mode shift down
signal InputIgnition
switch
ON Selector lever DOWN oper-
ation
0 V
Other than the above 12 V
39
(Y/B) Ground Manual mode shift up sig-
nal InputIgnition
switch
ON Selector lever UP operation 0 V
Other than the above 12 V
40
(G/W) Ground Manual mode signal Input Ignition
switch
ONSelector manual mode po-
sition
0 V
Other than the above 12 V
Te r m i n a l N o .
(Wire color) Description
ConditionVa l u e
(Approx.)
+ – Signal name Input/
Output
Function Specifications
Speedometer
Reset to zero by suspending communication.
Tachometer
Engine coolant temperature gauge
Engine oil pressure gauge
Illumination control When suspending communication, changes to nighttime mode.
Information display Odo/trip meter An indicated value is maintained at communications blackout.
Shift position indicator The display turns OFF by suspending communication.
Door open warning The display turns OFF by suspending communication.
Buzzer The buzzer turns OFF by suspending communication.
Revision: 2010 May2011 QX56

MWI
COMBINATION METERMWI-43
< ECU DIAGNOSIS INFORMATION >
C
DE
F
G H
I
J
K L
M B A
O P
DTC IndexINFOID:0000000006221723
Warning lamp/indicator lamp ABS warning lamp
The lamp turns ON by suspending communication.
VDC warning lamp
Brake warning lamp
IBA OFF indicator lamp
4WD warning lamp
Malfunction indicator lamp
VDC OFF indicator lamp
CRUISE warning lamp
Low tire pressure warning lamp The lamp blinking caused by suspending communication.
High beam indicator lamp
The lamp turns OFF by suspending communication.
Turn signal indicator lamp
Tail lamp indicator lamp
A/T CHECK indicator lamp
Key warning lamp
AT P w a r n i n g l a m p
Lane departure warning lamp
LDP ON indicator lamp
CRUISE indicator lamp
Oil pressure warning lamp
SNOW mode indicator lamp
TOW mode indicator lamp
CK SUSP indicator lamp
BSW indicator lamp
Function Specifications
Display contents of CONSULT-III Diagnostic item is detected when... Refer to
CAN COMM CIRCUIT
[U1000] When combination meter is not transmitting or receiving CAN communication signal
for 2 seconds or more. MWI-59,
"Diagnosis
Procedure"
CONTROL UNIT (CAN)
[U1010]
When detecting error during the initial diagnosis of the CAN controller of combina-
tion meter. MWI-60, "Diagnosis
Procedure"
VEHICLE SPEED
[B2205]
The abnormal vehicle speed signal is input from the ABS actuator and electric unit
(control unit) for
2 seconds or more. MWI-61, "Diagnosis
Procedure"
ENGINE SPEED
[B2267]
If ECM continuously transmits abnormal engine speed signals for 2 seconds or
more. MWI-62, "Diagnosis
Procedure"
WATER TEMP
[B2268]
If ECM continuously transmits abnormal engine coolant temperature signals for 60
seconds or more. MWI-63, "Diagnosis
Procedure"
Revision: 2010 May2011 QX56

MWI-44
< ECU DIAGNOSIS INFORMATION >
IPDM E/R
IPDM E/R
List of ECU ReferenceINFOID:0000000006221724
ECU Reference
IPDM E/R PCS-15, "
Reference Value"
PCS-21, "Fail-Safe"
PCS-22, "DTCIndex"
Revision: 2010 May2011 QX56

PCS
PCS-1
ELECTRICAL & POWER CONTROL
C
DE
F
G H
I
J
K L
B
SECTION PCS
A
O P
N
CONTENTS
POWER CONTROL SYSTEM
IPDM E/R
PRECAUTION ................ ...............................
3
PRECAUTIONS .............................................. .....3
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
3
SYSTEM DESCRIPTION ..............................4
COMPONENT PARTS ................................... .....4
Component Parts Location .................................. ......4
SYSTEM ..............................................................5
RELAY CONTROL SYSTEM ................................ ......5
RELAY CONTROL SYSTEM : System Diagram ......5
RELAY CONTROL SYSTEM : System Descrip-
tion ...................................................................... ......
5
RELAY CONTROL SYSTEM : Fail-Safe ...................6
POWER CONTROL SYSTEM .....................................7
POWER CONTROL SYSTEM : System Diagram ......8
POWER CONTROL SYSTEM : System Descrip-
tion ...................................................................... ......
8
SIGNAL BUFFER SYSTEM ........................ ................8
SIGNAL BUFFER SYSTEM : System Diagram .. ......8
SIGNAL BUFFER SYSTEM : System Description ......8
POWER CONSUMPTION CONTROL SYSTEM ... ......8
POWER CONSUMPTION CONTROL SYSTEM :
System Diagram ........................................................
9
POWER CONSUMPTION CONTROL SYSTEM :
System Description ...................................................
9
DIAGNOSIS SYSTEM (IPDM E/R) .....................10
Diagnosis Description ......................................... ....10
CONSULT-III Function (IPDM E/R) .........................12
ECU DIAGNOSIS INFORMATION ..............15
IPDM E/R ...........................................................15
Reference Value .................................................. ....15
Fail-Safe ..................................................................21
DTC Index ...............................................................22
WIRING DIAGRAM ......................................24
IPDM E/R ...........................................................24
Wiring Diagram .................................................... ....24
DTC/CIRCUIT DIAGNOSIS .........................28
U1000 CAN COMM CIRCUIT ...........................28
Description ........................................................... ....28
DTC Logic ................................................................28
Diagnosis Procedure ...............................................28
B2098 IGNITION RELAY ON STUCK ..............29
Description ...............................................................29
DTC Logic ................................................................29
Diagnosis Procedure ...............................................29
B2099 IGNITION RELAY OFF STUCK ............30
Description ...............................................................30
DTC Logic ................................................................30
Diagnosis Procedure ...............................................30
POWER SUPPLY AND GROUND CIRCUIT ....31
Diagnosis Procedure ...............................................31
REMOVAL AND INSTALLATION ...............32
IPDM E/R ...........................................................32
Removal and Installation ..................................... ....32
POWER DISTRIBUTION SYSTEM
PRECAUTION ............... ...............................
33
PRECAUTIONS .................................................33
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ....
33
Revision: 2010 May2011 QX56

PCS-2
Precaution Necessary for Steering Wheel Rota-
tion after Battery Disconnect ..................................
33
SYSTEM DESCRIPTION ............................35
COMPONENT PARTS .................................... ...35
Component Parts Location .................................. ...35
Component Description .........................................35
BCM ........................................................................35
Ignition Relay ..........................................................35
Accessory Relay .....................................................36
Blower Relay ..........................................................36
Push-Button Ignition Switch ....................................36
SYSTEM .......................................................... ...37
POWER DISTRIBUTION SYST EM ........................ ...37
POWER DISTRIBUTION SYSTEM : System Dia-
gram .................................................................... ...
37
POWER DISTRIBUTION SYSTEM : System De-
scription ..................................................................
37
DIAGNOSIS SYSTEM (BCM) ............................39
COMMON ITEM ..................................................... ...39
COMMON ITEM : CONSULT-III Function (BCM -
COMMON ITEM) ................................................. ...
39
INTELLIGENT KEY ................................................ ...40
INTELLIGENT KEY : CONSULT-III Function
(BCM - INTELLIGENT KEY) ...................................
40
ECU DIAGNOSIS INFO RMATION ..............45
BCM ................................................................ ...45
List of ECU Reference ......................................... ...45
WIRING DIAGRAM .....................................46
POWER DISTRIBUTION SYSTEM ................ ...46
Wiring Diagram .................................................... ...46
BASIC INSPECTION ...................................53
DIAGNOSIS AND REPAIR WORK FLOW ..... ...53
Work Flow ............................................................ ...53
DTC/CIRCUIT DIAGNOSIS ...................... ...56
B2614 ACC RELAY CIRCUIT ........................ ...56
DTC Logic ............................................................ ...56
Diagnosis Procedure ..............................................56
Component Inspection ............................................57
B2615 BLOWER RELAY CIRCUIT ...................59
DTC Logic ............................................................ ...59
Diagnosis Procedure ..............................................59
Component Inspection ......................................... ...60
B2616 IGNITION RELAY CIRCUIT ...................61
DTC Logic ............................................................ ...61
Diagnosis Procedure ...............................................61
Component Inspection ............................................62
B2618 BCM .......................................................63
DTC Logic ............................................................ ...63
Diagnosis Procedure ...............................................63
B261A PUSH-BUTTON IGNITION SWITCH .....64
DTC Logic ............................................................ ...64
Diagnosis Procedure ...............................................64
B26F1 IGNITION RELAY ..................................66
DTC Logic ............................................................ ...66
Diagnosis Procedure ...............................................66
B26F2 IGNITION RELAY ..................................68
DTC Logic ............................................................ ...68
Diagnosis Procedure ...............................................68
B26F6 BCM .......................................................70
DTC Logic ............................................................ ...70
Diagnosis Procedure ...............................................70
PUSH-BUTTON IGNITION SWITCH .................71
Component Function Check ............................... ...71
Diagnosis Procedure ...............................................71
Component Inspection ............................................72
PUSH-BUTTON IGNITION SWITCH POSI-
TION INDICATOR ..............................................
74
Description ........................................................... ...74
Component Function Check ..................................74
Diagnosis Procedure ...............................................74
SYMPTOM DIAGNOSIS ............................76
PUSH-BUTTON IGNITION SWITCH DOES
NOT OPERATE .............................................. ...
76
Description ........................................................... ...76
Diagnosis Procedure ...............................................76
PUSH-BUTTON IGNITION SWITCH POSI-
TION INDICATOR DOES NOT ILLUMINATE ...
77
Description ..............................................................77
Diagnosis Procedure ...............................................77
REMOVAL AND INSTALLATION ..............78
PUSH-BUTTON IGNITION SWITCH .............. ...78
Exploded View ..................................................... ...78
Removal and Installation .........................................78
Revision: 2010 May2011 QX56

PCS-8
< SYSTEM DESCRIPTION >[IPDM E/R]
SYSTEM
POWER CONTROL SYSTEM : System Diagram
INFOID:0000000006220164
POWER CONTROL SYSTEM : System DescriptionINFOID:0000000006220165
COOLING FAN CONTROL
IPDM E/R outputs cooling fan control signal (PWM signal ) to the electrically-controlled cooling fan coupling
according to the status of the cooling fan speed request signal received from ECM via CAN communication.
Refer to EC-41, "
COOLING FAN CONTROL : System Diagram".
ALTERNATOR CONTROL
IPDM E/R outputs power generation command signal (PWM signal ) to the alternator according to the status of
the power generation command value signal received from ECM via CAN communication. Refer to CHG-7,
"POWER GENERATION VOLTAGE VARIABLE CONTROL SYSTEM : System Diagram".
SIGNAL BUFFER SYSTEM
SIGNAL BUFFER SYSTEM : System DiagramINFOID:0000000006220166
SIGNAL BUFFER SYSTEM : System DescriptionINFOID:0000000006220167
 IPDM E/R reads the status of the oil pressure switch and transmits the oil pressure switch signal to BCM via
CAN communication. Refer to MWI-15, "
OIL PRESSURE WARNING LAMP : System Diagram".
 IPDM E/R reads the status of the hood switch and tr ansmits the hood switch signal to BCM via CAN commu-
nication. Refer to SEC-17, "
VEHICLE SECURITY SYSTEM : System Diagram".
 IPDM E/R receives the rear window defogger control signal from BCM via CAN communication and trans- mits it to ECM and AV control unit via CAN communication. Refer to DEF-6, "
System Diagram".
POWER CONSUMPTION CONTROL SYSTEM
JMMIA0491GB
JPMIA0952GB
Revision: 2010 May2011 QX56