2005 INFINITI QX4 fuel pressure

COMBINATION METERS
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COMBINATION METERSPFP:24814
System DescriptionEKS00BBU
UNIFIED METER CONTROL UNIT

Speedometer, odometer, tachometer, fuel gauge, oil pressure gauge, voltage gauge and water tempera-
ture gauge are controlled by the unified meter control unit, which is built into the combination meter.

Warning indicators are controlled by signals drawn from the CAN communication system, BCM (body con-
trol module), and components connected directly to the combination meter.

Digital meter is adopted for odometer/trip meters*, as well as the A/T position indicator display.
*The record of the odometer is kept even if the battery cable is disconnected.

Odometer/trip meters and A/T indicator segments can be checked in diagnosis mode.

Meters/gauges can be checked in diagnosis mode.
Illumination control
The unified meter control unit outputs the speedometer, odometer/trip meters, tachometer, oil pressure gauge,
voltage gauge, A/T indicator, fuel and temperature gauge lighting when the ignition switch is turned on. When
the lighting switch is turned on, the illumination control switch can be used to adjust the brightness of the com-
bination meter illumination and the odometer/trip meters and meter illumination. When the ignition switch is
turned from the OFF to the ON position, the combination meter dial lighting will remain off for 0.7 seconds. For
additional combination meter illumination control information, refer to LT-152, "
System Description" .

DI-6
COMBINATION METERS
Revision: October 20052005 QX56
POWER SUPPLY AND GROUND CIRCUIT
Power is supplied at all times

through 10A fuse [No.19, located in the fuse block (J/B)]

to combination meter terminal 8.
With the ignition switch in the ON or START position, power is supplied

through 10A fuse [No.14, located in the fuse block (J/B)]

to combination meter terminal 24.
With the ignition switch in the ACC or ON position, power is supplied

through 10A fuse [No.4, located in the fuse block (J/B)]

to combination meter terminal 1.
Ground is supplied

to combination meter terminal 17

through body grounds M57, M61 and M79.
WATER TEMPERATURE GAUGE
The water temperature gauge indicates the engine coolant temperature.
ECM provides an engine coolant temperature signal to combination meter via CAN communication lines.
ENGINE OIL PRESSURE GAUGE
The engine oil pressure gauge indicates the engine oil pressure.
The engine oil pressure gauge is regulated by the unified meter control unit and input from the oil pressure
sensor.
A/T OIL TEMPERATURE GAUGE
The A/T oil temperature gauge indicates the A/T fluid temperature.
TCM (transmission control module) provides an A/T fluid temperature signal to combination meter via CAN
communication lines.
V O LTA G E G A U G E
The voltage gauge indicates the battery/charging system voltage.
The voltage gauge is regulated by the unified meter control unit.
TACHOMETER
The tachometer indicates engine speed in revolutions per minute (rpm).
ECM provides an engine speed signal to combination meter via CAN communication lines.
FUEL GAUGE
The fuel gauge indicates the approximate fuel level in the fuel tank.
The fuel gauge is regulated by the unified meter control unit and a variable resistor signal supplied

to combination meter terminal 15

through fuel level sensor unit and fuel pump terminal 2

through fuel level sensor unit and fuel pump terminal 5

from combination meter terminal 16.
SPEEDOMETER
ABS actuator and electric unit (control unit) provides a vehicle speed signal to the combination meter via CAN
communication lines.
CAN COMMUNICATION SYSTEM DESCRIPTION
Refer to LAN-5, "CAN COMMUNICATION" .

COMBINATION METERS
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Component Parts and Harness Connector LocationEKS00BBV
1. Combination meter M24 2. Fuel level sensor unit and fuel pump
C5 (view with fuel tank removed)3. ECM
(view with battery removed)
4. ECM harness connector E16 5. ABS actuator and electric unit (con-
trol unit) E1256. Oil pressure sensor F4
7. A. Oil pan (upper) 8. A/T assembly F9
LKIA0691E

DI-12
COMBINATION METERS
Revision: October 20052005 QX56
Terminals and Reference Value for Combination MeterEKS00BBZ
Te r m i n a l
No.Wire
colorItemCondition
Reference value (V)
(Approx.) Ignition
switchOperation or condition
1OIgnition switch ACC or
ONACC — Battery voltage
8 Y/R Battery power supply OFF — Battery voltage
11 L C A N - H — — —
12 P CAN-L — — —
15 Y/L Fuel level sensor signal — —Refer to DI-22, "
Fuel Level Sensor
Unit Inspection" .
16 B/PFuel level sensor and oil
pressure sensor groundON — 0V
17 B Ground OFF — 0V
18 BR Illumination control switch — Lighting switch ONRefer to LT-153, "
ILLUMINATION
OPERATION BY LIGHTING
SWITCH" .
20 YOil pressure sensor sig-
nalON — 0 - 5V
22 GR/LOil pressure sensor refer-
ence voltageON — 5V
24 O/LIgnition switch ON or
STARTON — Battery voltage

DI-14
COMBINATION METERS
Revision: October 20052005 QX56
Next test requested Sc1XXDisplays 8-bit software
configuration value in Hex
format.Bit Coding
7-3 = reserved for future use
2 = TCS/VDC 0 = not present
1 = present
1 = Shift type 0 = Column shift
1 = Floor shift
0 = ICC 0 = not present
1 = present
Next test requested Sc2XXDisplays 8-bit software
configuration value in Hex
format.Bit coding
7-0 = Reserved for future use
Next test requested EprXXDisplays 8-bit software
configuration value in Hex
format.Bit Coding
7-2 = reserved for future use
1 = A/T Oil Temp (gauge)
0 = not present
1 = present
1 = Odo Units 0 = kilometers
1 = miles
Next test requested 1nFXXDisplays 8-bit market info
value in Hex format.$31 = USA
$2A = Canada
$0E = GCC
Next test requested cYLXXDisplays 8-bit engine con-
figuration value in Hex
format.$08 = 8 cylinder
$06 = 6 cylinder
Next test requested FFXXXXDisplays 16-bit fuel flow
constant "Q" in tenths of
cc/min in Hex format.$0000 - $FFFF
Next test requested tFDisplays 16-bit tire factor
"A" in hundredths in Hex
format.$0000 - $FFFF
Next test requested ot1XXDisplays oil pressure tell-
tale "on" threshold in A/D
counts in Hex format.$00 - $FF
Next test requested ot0XXDisplays oil pressure tell-
tale "off" threshold in A/D
counts in Hex format.$00 - $FF
Next test requested XXXXXRaw uncompensated
english speed value in
hundredths of MPH.
Speedometer indicates
present speed.Will display "-----" if message is
not received. Will display
"99999" if data received is
invalid
Next test requested XXXXXRaw uncompensated
metric speed value in
hundredths of KPH.
Speedometer indicates
present speed.Will display "-----" if message is
not received. Will display
"99999" if data received is
invalid
Next test requested tXXXXTachometer value in
RPM. Tachometer indi-
cates present RPM.Will display "-----" if message is
not received.
Next test requested F1 XXXXPresent ratioed fuel level
A/D input 1 in decimal for-
mat. Fuel gauge indicates
present filtered level.000-009 = Short circuit
010-254 = Normal range
255 = Open circuit
--- = Missing 5 seconds
Next test requested XXXCLast temperature gauge
input value in degrees C.
Temperature gauge indi-
cates present filtered tem-
perature.Will display "---"C if message is
not received.
Will display "999" if data
received is invalid. Event Odometer Display Description of Test/Data Notes:

COMBINATION METERS
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Symptom ChartEKS00BC4
Vehicle Speed Signal InspectionEKS00BC5
1. CHECK ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) SELF-DIAGNOSIS
Refer to BRC-29, "
SELF-DIAGNOSIS" .
OK or NG
OK >> Replace the combination meter. Refer to IP-13, "Combination Meter" .
NG >> Perform the "Diagnostic Procedure" for displayed DTC. Refer to BRC-11, "
TROUBLE DIAGNO-
SIS" .
Engine Oil Pressure Signal Inspection EKS00BC6
1. CHECK OIL PRESSURE SENSOR SIGNAL
1. Turn ignition switch ON.
2. Check voltage between combination meter harness connector
M24 terminal 20 (Y) and ground.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
Trouble phenomenon Possible cause
Improper tachometer indication. Refer to DI-21, "
Engine Speed Signal Inspection" .
Improper water temperature gauge indication. Refer to DI-21, "
Water Temperature Signal Inspection" .
Improper speedometer or odometer. Refer to DI-19, "
Vehicle Speed Signal Inspection" .
Improper fuel gauge indication.
Refer to DI-22, "
Fuel Level Sensor Unit Inspection" .
Fuel warning lamp indication is irregular.
Improper A/T oil temperature gauge indicationRefer to AT-126, "
DTC P1710 A/T FLUID TEMPERATURE SEN-
SOR CIRCUIT" .
Improper voltage gauge indication
Replace combination meter. Refer to IP-13, "
Combination Meter"
.
More than one gauge does not give proper indication.
Improper A/T position indication. Refer to DI-40, "
A/T INDICATOR" .
Illumination control does not operate properly. Refer to LT-152, "
ILLUMINATION" .
Te r m i n a l s
Condition Voltage (V) (+)
(–)
ConnectorTe r m i n a l
(Wire color)
M24 20 (Y) GroundWhen ignition switch is in ON
position. (Engine stopped)Ye s
Engine running. (Idle speed) Yes
WKIA1833E

EC-1
ENGINE CONTROL SYSTEM
B ENGINE
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SECTION EC
A
EC
Revision: October 20052005 QX56 INDEX FOR DTC ........................................................ 8
DTC No. Index ......................................................... 8
Alphabetical Index .................................................. 12
PRECAUTIONS ........................................................ 16
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ................................................................ 16
On Board Diagnostic (OBD) System of Engine and
A/T .......................................................................... 16
Precaution .............................................................. 16
Wiring Diagrams and Trouble Diagnosis ................ 19
PREPARATION ......................................................... 20
Special Service Tools ............................................. 20
Commercial Service Tools ...................................... 22
ENGINE CONTROL SYSTEM .................................. 23
System Diagram ..................................................... 23
Multiport Fuel Injection (MFI) System .................... 24
Electronic Ignition (EI) System ............................... 26
Fuel Cut Control (at No Load and High Engine
Speed) .................................................................... 27
AIR CONDITIONING CUT CONTROL ..................... 28
Input/Output Signal Chart ....................................... 28
System Description ................................................ 28
AUTOMATIC SPEED CONTROL DEVICE (ASCD) ... 29
System Description ................................................ 29
Component Description .......................................... 30
CAN COMMUNICATION .......................................... 31
System Description ................................................ 31
EVAPORATIVE EMISSION SYSTEM ....................... 32
Description ............................................................. 32
Component Inspection ........................................... 35
Removal and Installation ........................................ 36
How to Detect Fuel Vapor Leakage ....................... 37
ON BOARD REFUELING VAPOR RECOVERY
(ORVR) ...................................................................... 39
System Description ................................................ 39
Diagnostic Procedure ............................................. 40
Component Inspection ........................................... 43
POSITIVE CRANKCASE VENTILATION ................. 45Description .............................................................. 45
Component Inspection ............................................ 45
IVIS (INFINITI VEHICLE IMMOBILIZER SYSTEM-
NATS) ........................................................................ 47
Description .............................................................. 47
ON BOARD DIAGNOSTIC (OBD) SYSTEM ............ 48
Introduction ............................................................. 48
Two Trip Detection Logic ........................................ 48
Emission-related Diagnostic Information ................ 49
Malfunction Indicator Lamp (MIL) ........................... 64
OBD System Operation Chart ................................ 66
BASIC SERVICE PROCEDURE ............................... 72
Basic Inspection ..................................................... 72
Idle Speed and Ignition Timing Check .................... 77
Idle Mixture Ratio Adjustment ................................. 79
VIN Registration ..................................................... 90
Accelerator Pedal Released Position Learning ...... 90
Throttle Valve Closed Position Learning ................. 90
Idle Air Volume Learning ........................................ 91
Fuel Pressure Check .............................................. 93
TROUBLE DIAGNOSIS ............................................ 95
Trouble Diagnosis Introduction ............................... 95
DTC Inspection Priority Chart ...............................101
Fail-safe Chart ......................................................103
Symptom Matrix Chart ..........................................104
Engine Control Component Parts Location ..........108
Vacuum Hose Drawing .........................................114
Circuit Diagram .....................................................115
ECM Harness Connector Terminal Layout ...........117
ECM Terminals and Reference Value ...................117
CONSULT-II Function (ENGINE) ..........................126
Generic Scan Tool (GST) Function .......................139
CONSULT-II Reference Value in Data Monitor .....141
Major Sensor Reference Graph in Data Monitor
Mode .....................................................................144
TROUBLE DIAGNOSIS - SPECIFICATION VALUE .146
Description ............................................................146
Testing Condition ..................................................146
Inspection Procedure ............................................146
Diagnostic Procedure ...........................................147

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ECA
Revision: October 20052005 QX56 DTC P0172, P0175 FUEL INJECTION SYSTEM
FUNCTION .............................................................. 245
On Board Diagnosis Logic ................................... 245
DTC Confirmation Procedure ............................... 245
Wiring Diagram .................................................... 247
Diagnostic Procedure ........................................... 249
DTC P0181 FTT SENSOR ...................................... 253
Component Description ........................................ 253
On Board Diagnosis Logic ................................... 253
DTC Confirmation Procedure ............................... 253
Wiring Diagram .................................................... 255
Diagnostic Procedure ........................................... 256
Component Inspection ......................................... 258
Removal and Installation ...................................... 258
DTC P0182, P0183 FTT SENSOR ......................... 259
Component Description ........................................ 259
On Board Diagnosis Logic ................................... 259
DTC Confirmation Procedure ............................... 259
Wiring Diagram .................................................... 260
Diagnostic Procedure ........................................... 261
Component Inspection ......................................... 263
Removal and Installation ...................................... 263
DTC P0222, P0223 TP SENSOR ........................... 264
Component Description ........................................ 264
CONSULT-II Reference Value in Data Monitor Mode
. 264
On Board Diagnosis Logic ................................... 264
DTC Confirmation Procedure ............................... 265
Wiring Diagram .................................................... 266
Diagnostic Procedure ........................................... 267
Component Inspection ......................................... 270
Removal and Installation ...................................... 270
DTC P0300 - P0308 MULTIPLE CYLINDER MIS-
FIRE, NO. 1 - 8 CYLINDER MISFIRE ..................... 271
On Board Diagnosis Logic ................................... 271
DTC Confirmation Procedure ............................... 271
Diagnostic Procedure ........................................... 272
DTC P0327, P0328, P0332, P0333 KS .................. 279
Component Description ........................................ 279
On Board Diagnosis Logic ................................... 279
DTC Confirmation Procedure ............................... 279
Wiring Diagram .................................................... 280
Diagnostic Procedure ........................................... 281
Component Inspection ......................................... 283
Removal and Installation ...................................... 283
DTC P0335 CKP SENSOR (POS) .......................... 284
Component Description ........................................ 284
CONSULT-II Reference Value in Data Monitor Mode
. 284
On Board Diagnosis Logic ................................... 284
DTC Confirmation Procedure ............................... 284
Wiring Diagram .................................................... 286
Diagnostic Procedure ........................................... 287
Component Inspection ......................................... 290
Removal and Installation ...................................... 290
DTC P0340 CMP SENSOR (PHASE) ..................... 291
Component Description ........................................ 291
On Board Diagnosis Logic ................................... 291
DTC Confirmation Procedure ............................... 291Wiring Diagram .....................................................293
Diagnostic Procedure ...........................................294
Component Inspection ..........................................297
Removal and Installation ......................................297
DTC P0420, P0430 THREE WAY CATALYST FUNC-
TION ........................................................................298
On Board Diagnosis Logic ....................................298
DTC Confirmation Procedure ...............................298
Overall Function Check ........................................299
Diagnostic Procedure ...........................................300
DTC P0441 EVAP CONTROL SYSTEM .................304
System Description ...............................................304
On Board Diagnosis Logic ....................................304
DTC Confirmation Procedure ...............................304
Overall Function Check ........................................305
Diagnostic Procedure ...........................................306
DTC P0442 EVAP CONTROL SYSTEM .................309
On Board Diagnosis Logic ....................................309
DTC Confirmation Procedure ...............................310
Diagnostic Procedure ...........................................311
DTC P0444, P0445 EVAP CANISTER PURGE VOL-
UME CONTROL SOLENOID VALVE ......................318
Description ............................................................318
CONSULT-II Reference Value in Data Monitor Mode
.318
On Board Diagnosis Logic ....................................319
DTC Confirmation Procedure ...............................319
Wiring Diagram .....................................................320
Diagnostic Procedure ...........................................322
Component Inspection ..........................................323
Removal and Installation ......................................324
DTC P0447 EVAP CANISTER VENT CONTROL
VALVE .....................................................................325
Component Description ........................................325
CONSULT-II Reference Value in Data Monitor Mode
.325
On Board Diagnosis Logic ....................................325
DTC Confirmation Procedure ...............................326
Wiring Diagram .....................................................327
Diagnostic Procedure ...........................................328
Component Inspection ..........................................330
DTC P0451 EVAP CONTROL SYSTEM PRESSURE
SENSOR .................................................................332
Component Description ........................................332
CONSULT-II Reference Value in Data Monitor Mode
.332
On Board Diagnosis Logic ....................................332
DTC Confirmation Procedure ...............................333
Diagnostic Procedure ...........................................333
Component Inspection ..........................................334
DTC P0452 EVAP CONTROL SYSTEM PRESSURE
SENSOR .................................................................335
Component Description ........................................335
CONSULT-II Reference Value in Data Monitor Mode
.335
On Board Diagnosis Logic ....................................335
DTC Confirmation Procedure ...............................336
Wiring Diagram .....................................................337