EC-1
ENGINE CONTROL SYSTEM
B ENGINE
CONTENTS
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SECTION EC
A
EC
Revision: 2004 November 2004 FX35/FX45
ENGINE CONTROL SYSTEM
VQ35DE
INDEX FOR DTC ...................................................... 15
Alphabetical Index .................................................. 15
DTC No. Index ....................................................... 19
PRECAUTIONS ........................................................ 23
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ................................................................ 23
On Board Diagnostic (OBD) System of Engine and
A/T .......................................................................... 23
Precaution .............................................................. 23
Wiring Diagrams and Trouble Diagnosis ................ 26
PREPARATION ......................................................... 27
Special Service Tools ............................................. 27
Commercial Service Tools ...................................... 28
ENGINE CONTROL SYSTEM .................................. 29
System Diagram ..................................................... 29
Vacuum Hose Drawing ........................................... 30
System Chart ......................................................... 31
Multiport Fuel Injection (MFI) System .................... 32
Electronic Ignition (EI) System ............................... 34
Air Conditioning Cut Control ................................... 35
Fuel Cut Control (at No Load and High Engine
Speed) .................................................................... 35
CAN communication .............................................. 36
BASIC SERVICE PROCEDURE .............................. 37
Idle Speed and Ignition Timing Check .................... 37
Idle Speed/Ignition Timing/Idle Mixture Ratio
Adjustment ............................................................. 38
Accelerator Pedal Released Position Learning ...... 49
Throttle Valve Closed Position Learning ................ 49
Idle Air Volume Learning ........................................ 49
Fuel Pressure Check .............................................. 51
ON BOARD DIAGNOSTIC (OBD) SYSTEM ............ 53
Introduction ............................................................ 53
Two Trip Detection Logic ........................................ 53
Emission-Related Diagnostic Information .............. 54
IVIS (Infiniti Vehicle Immobilizer System — NATS) ... 68
Malfunction Indicator Lamp (MIL) ........................... 68
OBD System Operation Chart ................................ 72TROUBLE DIAGNOSIS ............................................ 77
Trouble Diagnosis Introduction ............................... 77
DTC Inspection Priority Chart ................................. 80
Fail-Safe Chart ....................................................... 82
Basic Inspection ..................................................... 83
Symptom Matrix Chart ............................................ 88
Engine Control Component Parts Location ............ 92
Circuit Diagram ....................................................... 98
ECM Harness Connector Terminal Layout ...........100
ECM Terminals and Reference Value ...................100
CONSULT-II Function ...........................................109
Generic Scan Tool (GST) Function .......................122
CONSULT-II Reference Value in Data Monitor .....125
Major Sensor Reference Graph in Data Monitor
Mode .....................................................................129
TROUBLE DIAGNOSIS - SPECIFICATION VALUE .131
Description ............................................................131
Testing Condition ..................................................131
Inspection Procedure ............................................131
Diagnostic Procedure ...........................................132
TROUBLE DIAGNOSIS FOR INTERMITTENT INCI-
DENT .......................................................................135
Description ............................................................135
Diagnostic Procedure ...........................................135
POWER SUPPLY AND GROUND CIRCUIT ...........136
Wiring Diagram .....................................................136
Diagnostic Procedure ...........................................137
Ground Inspection ................................................141
DTC U1000, U1001 CAN COMMUNICATION LINE .142
Description ............................................................142
On Board Diagnosis Logic ....................................142
DTC Confirmation Procedure ...............................142
Wiring Diagram .....................................................143
Diagnostic Procedure ...........................................144
DTC P0011, P0021 IVT CONTROL ........................145
Description ............................................................145
CONSULT-II Reference Value in Data Monitor Mode
.145
On Board Diagnosis Logic ....................................146
EC-7
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ECA
Revision: 2004 November 2004 FX35/FX45Component Inspection ......................................... 575
Removal and Installation ...................................... 575
DTC P2138 APP SENSOR ..................................... 576
Component Description ........................................ 576
CONSULT-II Reference Value in Data Monitor Mode
. 576
On Board Diagnosis Logic ................................... 576
DTC Confirmation Procedure ............................... 577
Wiring Diagram .................................................... 578
Diagnostic Procedure ........................................... 579
Component Inspection ......................................... 584
Removal and Installation ...................................... 584
IGNITION SIGNAL .................................................. 585
Component Description ........................................ 585
Wiring Diagram .................................................... 586
Diagnostic Procedure ........................................... 591
Component Inspection ......................................... 595
Removal and Installation ...................................... 596
INJECTOR CIRCUIT ............................................... 597
Component Description ........................................ 597
CONSULT-II Reference Value in Data Monitor Mode
. 597
Wiring Diagram .................................................... 598
Diagnostic Procedure ........................................... 599
Component Inspection ......................................... 602
Removal and Installation ...................................... 602
FUEL PUMP CIRCUIT ............................................ 603
Description ........................................................... 603
CONSULT-II Reference Value in Data Monitor Mode
. 603
Wiring Diagram .................................................... 604
Diagnostic Procedure ........................................... 605
Component Inspection ......................................... 608
Removal and Installation ...................................... 608
REFRIGERANT PRESSURE SENSOR ................. 609
Component Description ........................................ 609
Wiring Diagram .................................................... 610
Diagnostic Procedure ............................................ 611
Removal and Installation ...................................... 613
ELECTRICAL LOAD SIGNAL ................................ 614
Description ........................................................... 614
CONSULT-II Reference Value in Data Monitor Mode
. 614
Diagnostic Procedure ........................................... 614
ICC BRAKE SWITCH ............................................. 615
Component Description ........................................ 615
CONSULT-II Reference Value in Data Monitor Mode
. 615
Wiring Diagram .................................................... 616
Diagnostic Procedure ........................................... 617
Component Inspection ......................................... 622
ASCD BRAKE SWITCH ......................................... 624
Component Description ........................................ 624
CONSULT-II Reference Value in Data Monitor Mode
. 624
Wiring Diagram .................................................... 625
Diagnostic Procedure ........................................... 626
Component Inspection ......................................... 631ASCD INDICATOR ..................................................632
Component Description ........................................632
CONSULT-II Reference Value in Data Monitor Mode
.632
Wiring Diagram .....................................................633
Diagnostic Procedure ...........................................634
SNOW MODE SWITCH ..........................................635
Description ............................................................635
CONSULT-II Reference Value in the Data Monitor
Mode .....................................................................635
Wiring Diagram .....................................................636
Diagnostic Procedure ...........................................637
Component Inspection ..........................................640
MIL AND DATA LINK CONNECTOR ......................641
Wiring Diagram .....................................................641
EVAPORATIVE EMISSION SYSTEM .....................643
Description ............................................................643
Component Inspection ..........................................646
Removal and Installation ......................................647
How to Detect Fuel Vapor Leakage ......................647
ON BOARD REFUELING VAPOR RECOVERY
(ORVR) ....................................................................650
System Description ...............................................650
Diagnostic Procedure ...........................................651
Component Inspection ..........................................653
POSITIVE CRANKCASE VENTILATION ...............655
Description ............................................................655
Component Inspection ..........................................655
AUTOMATIC SPEED CONTROL DEVICE (ASCD) .657
System Description ...............................................657
Component Description ........................................659
SERVICE DATA AND SPECIFICATIONS (SDS) ....660
Fuel Pressure .......................................................660
Idle Speed and Ignition Timing .............................660
Calculated Load Value ..........................................660
Mass Air Flow Sensor ...........................................660
Intake Air Temperature Sensor .............................660
Engine Coolant Temperature Sensor ...................660
Heated Oxygen Sensor 1 Heater .........................660
Heated Oxygen sensor 2 Heater ..........................660
Crankshaft Position Sensor (POS) .......................660
Camshaft Position Sensor (PHASE) ....................660
Throttle Control Motor ...........................................660
Injector ..................................................................661
Fuel Pump ............................................................661
VK45DE
INDEX FOR DTC .....................................................662
Alphabetical Index ................................................662
DTC No. Index ......................................................665
PRECAUTIONS ......................................................670
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ...............................................................670
On Board Diagnostic (OBD) System of Engine and
A/T ........................................................................670
Precaution ............................................................670
Wiring Diagrams and Trouble Diagnosis ..............673
EC-8Revision: 2004 November 2004 FX35/FX45 PREPARATION .......................................................674
Special Service Tools ...........................................674
Commercial Service Tools ....................................675
ENGINE CONTROL SYSTEM ................................676
System Diagram ...................................................676
Vacuum Hose Drawing .........................................677
System Chart ........................................................678
Multiport Fuel Injection (MFI) System ...................679
Electronic Ignition (EI) System .............................681
Nissan Torque Demand (NTD) Control System ....682
Air Conditioning Cut Control .................................683
Fuel Cut Control (at No Load and High Engine
Speed) ..................................................................683
CAN communication .............................................684
BASIC SERVICE PROCEDURE .............................685
Idle Speed and Ignition Timing Check ..................685
Idle Speed/Ignition Timing/Idle Mixture Ratio
Adjustment ............................................................687
Accelerator Pedal Released Position Learning ....698
Throttle Valve Closed Position Learning ...............698
Idle Air Volume Learning ......................................698
Fuel Pressure Check ............................................700
ON BOARD DIAGNOSTIC (OBD) SYSTEM ..........703
Introduction ...........................................................703
Two Trip Detection Logic ......................................703
Emission-related Diagnostic Information ..............704
IVIS (Infiniti Vehicle Immobilizer System — NATS) .717
Malfunction Indicator Lamp (MIL) .........................717
OBD System Operation Chart ..............................721
TROUBLE DIAGNOSIS ..........................................726
Trouble Diagnosis Introduction .............................726
DTC Inspection Priority Chart ...............................729
Fail-safe Chart ......................................................731
Basic Inspection ...................................................733
Symptom Matrix Chart ..........................................738
Engine Control Component Parts Location ..........742
Circuit Diagram .....................................................748
ECM Harness Connector Terminal Layout ...........750
ECM Terminals and Reference Value ...................750
CONSULT-II Function ...........................................759
Generic Scan Tool (GST) Function .......................772
CONSULT-II Reference Value in Data Monitor .....775
Major Sensor Reference Graph in Data Monitor
Mode .....................................................................778
TROUBLE DIAGNOSIS - SPECIFICATION VALUE .780
Description ............................................................780
Testing Condition ..................................................780
Inspection Procedure ............................................780
Diagnostic Procedure ...........................................781
TROUBLE DIAGNOSIS FOR INTERMITTENT INCI-
DENT .......................................................................784
Description ............................................................784
Diagnostic Procedure ...........................................784
POWER SUPPLY AND GROUND CIRCUIT ...........785
Wiring Diagram .....................................................785
Diagnostic Procedure ...........................................786
Ground Inspection ................................................791
DTC U1000, U1001 CAN COMMUNICATION LINE .792
Description ............................................................792On Board Diagnosis Logic ....................................792
DTC Confirmation Procedure ................................792
Wiring Diagram .....................................................793
Diagnostic Procedure ............................................794
DTC P0011, P0021 IVT CONTROL .........................795
Description ............................................................795
CONSULT-II Reference Value in Data Monitor Mode
.796
On Board Diagnosis Logic ....................................796
DTC Confirmation Procedure ................................797
Wiring Diagram .....................................................798
Diagnostic Procedure ............................................801
Component Inspection ..........................................805
Removal and Installation .......................................805
DTC P0031, P0032, P0051, P0052 HO2S1 HEATER .806
Description ............................................................806
CONSULT-II Reference Value in Data Monitor Mode
.806
On Board Diagnosis Logic ....................................806
DTC Confirmation Procedure ................................807
Wiring Diagram .....................................................808
Diagnostic Procedure ............................................811
Component Inspection ..........................................813
Removal and Installation .......................................813
DTC P0037, P0038, P0057, P0058 HO2S2 HEATER .814
Description ............................................................814
CONSULT-II Reference Value in Data Monitor Mode
.814
On Board Diagnosis Logic ....................................814
DTC Confirmation Procedure ................................815
Wiring Diagram .....................................................816
Diagnostic Procedure ............................................819
Component Inspection ..........................................821
Removal and Installation .......................................821
DTC P0101 MAF SENSOR .....................................822
Component Description ........................................822
CONSULT-II Reference Value in Data Monitor Mode
.822
On Board Diagnosis Logic ....................................822
DTC Confirmation Procedure ................................823
Overall Function Check .........................................824
Wiring Diagram .....................................................825
Diagnostic Procedure ............................................826
Component Inspection ..........................................829
Removal and Installation .......................................829
DTC P0102, P0103 MAF SENSOR .........................830
Component Description ........................................830
CONSULT-II Reference Value in Data Monitor Mode
.830
On Board Diagnosis Logic ....................................830
DTC Confirmation Procedure ................................831
Wiring Diagram .....................................................832
Diagnostic Procedure ............................................833
Component Inspection ..........................................836
Removal and Installation .......................................836
DTC P0112, P0113 IAT SENSOR ............................837
Component Description ........................................837
On Board Diagnosis Logic ....................................837
DTC Confirmation Procedure ................................837
EC-14Revision: 2004 November 2004 FX35/FX45CONSULT-II Reference Value in Data Monitor Mode
1255
Wiring Diagram ....................................................1256
Diagnostic Procedure ..........................................1257
Component Inspection .........................................1260
Removal and Installation .....................................1261
IGNITION SIGNAL .................................................1262
Component Description .......................................1262
Wiring Diagram ....................................................1263
Diagnostic Procedure ..........................................1268
Component Inspection .........................................1272
Removal and Installation .....................................1273
INJECTOR CIRCUIT ..............................................1274
Component Description .......................................1274
CONSULT-II Reference Value in Data Monitor Mode
1274
Wiring Diagram ....................................................1275
Diagnostic Procedure ..........................................1276
Component Inspection .........................................1279
Removal and Installation .....................................1279
FUEL PUMP CIRCUIT ...........................................1280
Description ...........................................................1280
CONSULT-II Reference Value in Data Monitor Mode
1280
Wiring Diagram ....................................................1281
Diagnostic Procedure ..........................................1282
Component Inspection .........................................1285
Removal and Installation .....................................1286
REFRIGERANT PRESSURE SENSOR .................1287
Component Description .......................................1287
Wiring Diagram ....................................................1288
Diagnostic Procedure ..........................................1289
Removal and Installation .....................................1291
ELECTRICAL LOAD SIGNAL ...............................1292
Description ...........................................................1292
CONSULT-II Reference Value in Data Monitor Mode
1292
Diagnostic Procedure ..........................................1292
ICC BRAKE SWITCH .............................................1293
Component Description .......................................1293
CONSULT-II Reference Value in Data Monitor Mode
1293
Wiring Diagram ....................................................1294
Diagnostic Procedure ..........................................1295
Component Inspection .........................................1301
ASCD BRAKE SWITCH .........................................1302
Component Description .......................................1302
CONSULT-II Reference Value in Data Monitor Mode
1302Wiring Diagram ....................................................1303
Diagnostic Procedure ...........................................1304
Component Inspection .........................................1308
ASCD INDICATOR .................................................1309
Component Description .......................................1309
CONSULT-II Reference Value in Data Monitor Mode
1309
Wiring Diagram ....................................................1310
Diagnostic Procedure ...........................................1311
SNOW MODE SWITCH ..........................................1312
Description ...........................................................1312
CONSULT-II Reference Value in the Data Monitor
Mode ....................................................................1312
Wiring Diagram ....................................................1313
Diagnostic Procedure ...........................................1314
Component Inspection .........................................1317
MIL AND DATA LINK CONNECTOR .....................1318
Wiring Diagram ....................................................1318
EVAPORATIVE EMISSION SYSTEM ....................1320
Description ...........................................................1320
Component Inspection .........................................1323
Removal and Installation ......................................1324
How to Detect Fuel Vapor Leakage .....................1324
ON BOARD REFUELING VAPOR RECOVERY
(ORVR) ...................................................................1327
System Description ..............................................1327
Diagnostic Procedure ...........................................1328
Component Inspection .........................................1330
POSITIVE CRANKCASE VENTILATION ...............1332
Description ...........................................................1332
Component Inspection .........................................1332
AUTOMATIC SPEED CONTROL DEVICE (ASCD) 1334
System Description ..............................................1334
Component Description .......................................1335
SERVICE DATA AND SPECIFICATIONS (SDS) ...1336
Fuel Pressure .......................................................1336
Idle Speed and Ignition Timing .............................1336
Calculated Load Value .........................................1336
Mass Air Flow Sensor ..........................................1336
Intake Air Temperature Sensor ............................1336
Engine Coolant Temperature Sensor ...................1336
Heated Oxygen Sensor 1 Heater .........................1336
Heated Oxygen Sensor 2 Heater .........................1336
Crankshaft Position Sensor (POS) ......................1336
Camshaft Position Sensor (PHASE) ....................1336
Throttle Control Motor ..........................................1336
Injector .................................................................1337
Fuel Pump ............................................................1337
EC-34
[VQ35DE]
ENGINE CONTROL SYSTEM
Revision: 2004 November 2004 FX35/FX45
FUEL INJECTION TIMING
Two types of systems are used.
Sequential Multiport Fuel Injection System
Fuel is injected into each cylinder during each engine cycle according to the firing order. This system is used
when the engine is running.
Simultaneous Multiport Fuel Injection System
Fuel is injected simultaneously into all six cylinders twice each engine cycle. In other words, pulse signals of
the same width are simultaneously transmitted from the ECM.
The six injectors will then receive the signals two times for each engine cycle.
This system is used when the engine is being started and/or if the fail-safe system (CPU) is operating.
FUEL SHUT-OFF
Fuel to each cylinder is cut off during deceleration or operation of the engine at excessively high speeds.
Electronic Ignition (EI) SystemABS006K8
INPUT/OUTPUT SIGNAL CHART
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
The ignition timing is controlled by the ECM to maintain the best air-
fuel ratio for every running condition of the engine. The ignition tim-
ing data is stored in the ECM. This data forms the map shown.
The ECM receives information such as the injection pulse width and
camshaft position sensor signal. Computing this information, ignition
signals are transmitted to the power transistor.
e.g., N: 1,800 rpm, Tp: 1.50 msec
A °BTDC
During the following conditions, the ignition timing is revised by the
ECM according to the other data stored in the ECM.
At starting
During warm-up
SEF179U
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Engine speed*
2
Piston position
Ignition timing
controlPower transistor Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Knock sensor Engine knocking
Park/neutral position (PNP) switch Gear position
Battery
Battery voltage*
2
Wheel sensor*1Vehicle speed
SEF742M
ENGINE CONTROL SYSTEM
EC-35
[VQ35DE]
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At idle
At low battery voltage
During acceleration
The knock sensor retard system is designed only for emergencies. The basic ignition timing is programmed
within the anti-knocking zone, if recommended fuel is used under dry conditions. The retard system does not
operate under normal driving conditions. If engine knocking occurs, the knock sensor monitors the condition.
The signal is transmitted to the ECM. The ECM retards the ignition timing to eliminate the knocking condition.
Air Conditioning Cut ControlABS006K9
INPUT/OUTPUT SIGNAL CHART
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
This system improves engine operation when the air conditioner is used.
Under the following conditions, the air conditioner is turned off.
When the accelerator pedal is fully depressed.
When cranking the engine.
At high engine speeds.
When the engine coolant temperature becomes excessively high.
When operating power steering during low engine speed or low vehicle speed.
When engine speed is excessively low.
When refrigerant pressure is excessively low or high.
Fuel Cut Control (at No Load and High Engine Speed)ABS006KA
INPUT/OUTPUT SIGNAL CHART
*1: This signal is sent to the ECM through CAN communication line.
SYSTEM DESCRIPTION
If the engine speed is above 1,800 rpm under no load (for example, the shift position is neutral and engine
speed is over 1,800 rpm) fuel will be cut off after some time. The exact time when the fuel is cut off varies
based on engine speed.
Fuel cut will be operated until the engine speed reaches 1,500 rpm, then fuel cut will be cancelled.
Sensor Input Signal to ECM ECM function Actuator
Air conditioner switch*
1Air conditioner ON signal
Air conditioner
cut controlAir conditioner relay Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed*
2
Engine coolant temperature sensor Engine coolant temperature
Battery
Battery voltage*
2
Refrigerant pressure sensor Refrigerant pressure
Power steering pressure sensor Power steering operation
Wheel sensor*
1Vehicle speed
Sensor Input Signal to ECM ECM function Actuator
Park/neutral position (PNP) switch Neutral position
Fuel cut con-
trolFuel injector Accelerator pedal position sensor Accelerator pedal position
Engine coolant temperature sensor Engine coolant temperature
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed
Wheel sensor*
1Vehicle speed
BASIC SERVICE PROCEDURE
EC-37
[VQ35DE]
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Revision: 2004 November 2004 FX35/FX45
BASIC SERVICE PROCEDUREPFP:00018
Idle Speed and Ignition Timing CheckABS006KC
IDLE SPEED
With CONSULT-II
Check idle speed in “DATA MONITOR” mode with CONSULT-II.
With GST
Check idle speed with GST.
IGNITION TIMING
Any of following two methods may be used.
Method A
1. Attach timing light to loop wire as shown.
2. Check ignition timing.
Method B
1. Remove No. 1 ignition coil.
SEF058Y
PBIB1574E
PBIB1602E
PBIB1567E
EC-38
[VQ35DE]
BASIC SERVICE PROCEDURE
Revision: 2004 November 2004 FX35/FX45
2. Connect No. 1 ignition coil and No. 1 spark plug with suitable
high-tension wire as shown, and attach timing light clamp to this
wire.
3. Check ignition timing.
Idle Speed/Ignition Timing/Idle Mixture Ratio AdjustmentABS006KD
PREPARATION
1. Make sure that the following parts are in good order.
Battery
Ignition system
Engine oil and coolant levels
Fuses
ECM harness connector
Vacuum hoses
Air intake system
(Oil filler cap, oil level gauge, etc.)
Fuel pressure
Engine compression
Throttle valve
Evaporative emission system
2. On air conditioner equipped models, checks should be carried out while the air conditioner is OFF.
3. On automatic transmission equipped models, when checking idle rpm, ignition timing and mixture ratio,
checks should be carried out while shift lever is in N position.
4. When measuring CO percentage, insert probe more than 40 cm (15.7 in) into tail pipe.
5. Turn OFF headlamp, heater blower, rear window defogger.
PBIB1573E
SEF166Y
PBIB1602E