EC-1
ENGINE CONTROL SYSTEM
B ENGINE
CONTENTS
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SECTION EC
A
EC
Revision: 2007 April2007 M35/M45
ENGINE CONTROL SYSTEM
VQ35DE
INDEX FOR DTC ...................................................... 16
DTC No. Index ....................................................... 16
Alphabetical Index .................................................. 20
PRECAUTIONS ........................................................ 24
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ................................................................ 24
Precautions for Procedures without Cowl Top Cover ... 24
On Board Diagnostic (OBD) System of Engine and
A/T .......................................................................... 24
Precaution .............................................................. 25
PREPARATION ......................................................... 28
Special Service Tools ............................................. 28
Commercial Service Tools ...................................... 29
ENGINE CONTROL SYSTEM .................................. 30
System Diagram ..................................................... 30
Multiport Fuel Injection (MFI) System .................... 31
Electronic Ignition (EI) System ............................... 33
Fuel Cut Control (At No Load and High Engine
Speed) .................................................................... 34
AIR CONDITIONING CUT CONTROL ..................... 35
Input/Output Signal Chart ....................................... 35
System Description ................................................ 35
AUTOMATIC SPEED CONTROL DEVICE (ASCD) ... 36
System Description ................................................ 36
Component Description .......................................... 37
CAN COMMUNICATION .......................................... 38
System Description ................................................ 38
EVAPORATIVE EMISSION SYSTEM ....................... 39
Description ............................................................. 39
Component Inspection ........................................... 42
Removal and Installation ........................................ 43
How to Detect Fuel Vapor Leakage ....................... 43
ON BOARD REFUELING VAPOR RECOVERY
(ORVR) ...................................................................... 46
System Description ................................................ 46
Diagnostic Procedure ............................................. 47
Component Inspection ........................................... 49POSITIVE CRANKCASE VENTILATION ................. 51
Description .............................................................. 51
Component Inspection ............................................ 51
IVIS (INFINITI VEHICLE IMMOBILIZER SYSTEM-
NATS) ........................................................................ 53
Description .............................................................. 53
ON BOARD DIAGNOSTIC (OBD) SYSTEM ............ 54
Introduction ............................................................. 54
Two Trip Detection Logic ........................................ 54
Emission-Related Diagnostic Information ............... 55
Malfunction Indicator Lamp (MIL) ........................... 70
OBD System Operation Chart ................................ 73
BASIC SERVICE PROCEDURE ............................... 78
Basic Inspection ..................................................... 78
Idle Speed and Ignition Timing Check .................... 83
Procedure After Replacing ECM ............................ 85
VIN Registration ..................................................... 85
Accelerator Pedal Released Position Learning ...... 86
Throttle Valve Closed Position Learning ................. 86
Idle Air Volume Learning ........................................ 86
Fuel Pressure Check .............................................. 88
TROUBLE DIAGNOSIS ............................................ 90
Trouble Diagnosis Introduction ............................... 90
DTC Inspection Priority Chart ................................. 96
Fail-Safe Chart ....................................................... 98
Symptom Matrix Chart ............................................ 99
Engine Control Component Parts Location ..........103
Vacuum Hose Drawing ..........................................111
Circuit Diagram .....................................................112
ECM Harness Connector Terminal Layout ...........114
ECM Terminals and Reference Value ...................114
CONSULT-II Function (ENGINE) ..........................123
Generic Scan Tool (GST) Function .......................135
CONSULT-II Reference Value in Data Monitor .....138
Major Sensor Reference Graph in Data Monitor
Mode .....................................................................141
TROUBLE DIAGNOSIS - SPECIFICATION VALUE .143
Description ............................................................143
Testing Condition ..................................................143
EC-8Revision: 2007 April2007 M35/M45 .683
Wiring Diagram .....................................................684
Diagnostic Procedure ...........................................685
Component Inspection ..........................................689
IGNITION SIGNAL ..................................................691
Component Description ........................................691
Wiring Diagram .....................................................692
Diagnostic Procedure ...........................................697
Component Inspection ..........................................702
Removal and Installation ......................................703
REFRIGERANT PRESSURE SENSOR ..................704
Component Description ........................................704
Wiring Diagram .....................................................705
Diagnostic Procedure ...........................................706
Removal and Installation ......................................708
SNOW MODE SWITCH ...........................................709
Description ............................................................709
CONSULT-II Reference Value in the Data Monitor
Mode .....................................................................709
Wiring Diagram .....................................................710
Diagnostic Procedure ...........................................711
Component Inspection ..........................................713
MIL AND DATA LINK CONNECTOR ......................714
Wiring Diagram .....................................................714
SERVICE DATA AND SPECIFICATIONS (SDS) ....716
Fuel Pressure .......................................................716
Idle Speed and Ignition Timing .............................716
Calculated Load Value ..........................................716
Mass Air Flow Sensor ...........................................716
Intake Air Temperature Sensor .............................716
Engine Coolant Temperature Sensor ...................716
Fuel Tank Temperature Sensor ............................716
Crankshaft Position Sensor (POS) .......................716
Camshaft Position Sensor (PHASE) ....................716
A/F Sensor 1 Heater .............................................716
Heated Oxygen Sensor 2 Heater .........................717
Throttle Control Motor ...........................................717
Fuel Injector ..........................................................717
Fuel Pump ............................................................717
VK45DE
INDEX FOR DTC .....................................................718
DTC No. Index ......................................................718
Alphabetical Index ................................................722
PRECAUTIONS .......................................................726
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ...............................................................726
Precautions for Procedures without Cowl Top Cover .726
On Board Diagnostic (OBD) System of Engine and
A/T ........................................................................726
Precaution ............................................................727
PREPARATION .......................................................730
Special Service Tools ...........................................730
Commercial Service Tools ....................................731
ENGINE CONTROL SYSTEM ................................732
System Diagram ...................................................732
Multiport Fuel Injection (MFI) System ...................733Electronic Ignition (EI) System ..............................735
Fuel Cut Control (At No Load and High Engine
Speed) ..................................................................736
AIR CONDITIONING CUT CONTROL ....................737
Input/Output Signal Chart .....................................737
System Description ...............................................737
AUTOMATIC SPEED CONTROL DEVICE (ASCD) .738
System Description ...............................................738
Component Description ........................................739
CAN COMMUNICATION .........................................740
System Description ...............................................740
EVAPORATIVE EMISSION SYSTEM .....................741
Description ............................................................741
Component Inspection ..........................................744
Removal and Installation .......................................745
How to Detect Fuel Vapor Leakage ......................745
ON BOARD REFUELING VAPOR RECOVERY
(ORVR) ....................................................................748
System Description ...............................................748
Diagnostic Procedure ............................................749
Component Inspection ..........................................751
POSITIVE CRANKCASE VENTILATION ................753
Description ............................................................753
Component Inspection ..........................................753
IVIS (INFINITI VEHICLE IMMOBILIZER SYSTEM-
NATS) ......................................................................755
Description ............................................................755
ON BOARD DIAGNOSTIC (OBD) SYSTEM ...........756
Introduction ...........................................................756
Two Trip Detection Logic .......................................756
Emission-Related Diagnostic Information .............757
Malfunction Indicator Lamp (MIL) .........................772
OBD System Operation Chart ...............................774
BASIC SERVICE PROCEDURE .............................780
Basic Inspection ....................................................780
Idle Speed and Ignition Timing Check ..................785
Procedure After Replacing ECM ...........................787
VIN Registration ....................................................787
Accelerator Pedal Released Position Learning .....788
Throttle Valve Closed Position Learning ...............788
Idle Air Volume Learning .......................................788
Fuel Pressure Check ............................................790
TROUBLE DIAGNOSIS ..........................................792
Trouble Diagnosis Introduction .............................792
DTC Inspection Priority Chart ...............................798
Fail-Safe Chart ......................................................800
Symptom Matrix Chart ..........................................801
Engine Control Component Parts Location ...........805
Vacuum Hose Drawing .........................................814
Circuit Diagram .....................................................815
ECM Harness Connector Terminal Layout ............817
ECM Terminals and Reference Value ...................817
CONSULT-II Function (ENGINE) ..........................826
Generic Scan Tool (GST) Function .......................838
CONSULT-II Reference Value in Data Monitor .....841
Major Sensor Reference Graph in Data Monitor
Mode .....................................................................845
TROUBLE DIAGNOSIS - SPECIFICATION VALUE .847
Description ............................................................847
EC-15
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ECA
Revision: 2007 April2007 M35/M45 Wiring Diagram ...................................................1390
Diagnostic Procedure ..........................................1391
Component Inspection ........................................1394
Removal and Installation .....................................1394
FUEL PUMP ..........................................................1395
Description ..........................................................1395
CONSULT-II Reference Value in Data Monitor Mode
1395
Wiring Diagram ...................................................1396
Diagnostic Procedure ..........................................1397
Component Inspection ........................................1401
Removal and Installation .....................................1402
ICC BRAKE SWITCH ............................................1403
Component Description .......................................1403
CONSULT-II Reference Value in Data Monitor Mode
1403
Wiring Diagram ...................................................1404
Diagnostic Procedure ..........................................1405
Component Inspection ........................................1410
IGNITION SIGNAL .................................................1411
Component Description .......................................1411
Wiring Diagram ...................................................1412
Diagnostic Procedure ..........................................1417
Component Inspection ........................................1421
Removal and Installation .....................................1423
REFRIGERANT PRESSURE SENSOR ................1424
Component Description .......................................1424
Wiring Diagram ...................................................1425Diagnostic Procedure ..........................................1426
Removal and Installation .....................................1428
VIAS .......................................................................1429
Description ...........................................................1429
CONSULT-II Reference Value in Data Monitor Mode
1430
Wiring Diagram ....................................................1431
Diagnostic Procedure ..........................................1433
Component Inspection .........................................1436
Removal and Installation .....................................1437
MIL AND DATA LINK CONNECTOR .....................1438
Wiring Diagram ....................................................1438
SERVICE DATA AND SPECIFICATIONS (SDS) ...1440
Fuel Pressure ......................................................1440
Idle Speed and Ignition Timing ............................1440
Calculated Load Value .........................................1440
Mass Air Flow Sensor ..........................................1440
Intake Air Temperature Sensor ............................1440
Engine Coolant Temperature Sensor ..................1440
Fuel Tank Temperature Sensor ...........................1440
Crankshaft Position Sensor (POS) ......................1440
Camshaft Position Sensor (PHASE) ...................1440
A/F Sensor 1 Heater ............................................1440
Heated Oxygen Sensor 2 Heater ........................1441
Throttle Control Motor ..........................................1441
Fuel Injector .........................................................1441
Fuel Pump ...........................................................1441
EC-24
[VQ35DE]
PRECAUTIONS
Revision: 2007 April2007 M35/M45
PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
NBS004RW
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 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 whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SRS and SB section of this Service Man-
ual.
WARNING:
To avoid rendering the SRS inoperative, 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 per-
formed by an authorized NISSAN/INFINITI dealer.
Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.
Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or
harness connectors.
Precautions for Procedures without Cowl Top CoverNBS004RX
When performing the procedure after removing cowl top cover, cover
the lower end of windshield with urethane, etc.
On Board Diagnostic (OBD) System of Engine and A/TNBS004RY
The ECM has an on board diagnostic system. It will light up the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:
Be sure to turn the ignition switch OFF and disconnect the negative battery cable before any
repair or inspection work. The open/short circuit of related switches, sensors, solenoid valves,
etc. will cause the MIL to light up.
Be sure to connect and lock the connectors securely after work. A loose (unlocked) connector will
cause the MIL to light up due to the open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
Certain systems and components, especially those related to OBD, may use a new style slide-
locking type harness connector. For description and how to disconnect, refer to PG-104, "
HAR-
NESS CONNECTOR" .
Be sure to route and secure the harnesses properly after work. The interference of the harness
with a bracket, etc. may cause the MIL to light up due to the short circuit.
Be sure to connect rubber tubes properly after work. A misconnected or disconnected rubber tube
may cause the MIL to light up due to the malfunction of the EVAP system or fuel injection system,
etc.
Be sure to erase the unnecessary malfunction information (repairs completed) from the ECM and
TCM (Transmission control module) before returning the vehicle to the customer.
PIIB3706J
PRECAUTIONS
EC-25
[VQ35DE]
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PrecautionNBS004RZ
Always use a 12 volt battery as power source.
Do not attempt to disconnect battery cables while engine is
running.
Before connecting or disconnecting the ECM harness con-
nector, turn ignition switch OFF and disconnect negative
battery cable. Failure to do so may damage the ECM
because battery voltage is applied to ECM even if ignition
switch is turned OFF.
Before removing parts, turn ignition switch OFF and then
disconnect negative battery cable.
Do not disassemble ECM.
If a battery cable is disconnected, the memory will return to
the ECM value.
The ECM will now start to self-control at its initial value.
Engine operation can vary slightly when the terminal is dis-
connected. However, this is not an indication of a malfunc-
tion. Do not replace parts because of a slight variation.
If the battery is disconnected, the following emission-
related diagnostic information will be lost within 24 hours.
–Diagnostic trouble codes
–1st trip diagnostic trouble codes
–Freeze frame data
–1st trip freeze frame data
–System readiness test (SRT) codes
–Test values
When connecting ECM harness connector, fasten (B) it
securely with a lever (2) as far as it will go as shown in the
figure.
–ECM (1)
–Loosen (A)
When connecting or disconnecting pin connectors into or
from ECM, take care not to damage pin terminals (bend or
break).
Make sure that there are not any bends or breaks on ECM
pin terminal, when connecting pin connectors.
Securely connect ECM harness connectors.
A poor connection can cause an extremely high (surge)
voltage to develop in coil and condenser, thus resulting in
damage to ICs.
Keep engine control system harness at least 10 cm (4 in)
away from adjacent harness, to prevent engine control sys-
tem malfunctions due to receiving external noise, degraded
operation of ICs, etc.
Keep engine control system parts and harness dry.
SEF289H
PBIB1164E
PBIB2714E
PBIB0090E
ENGINE CONTROL SYSTEM
EC-33
[VQ35DE]
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EC
Revision: 2007 April2007 M35/M45
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 fuel 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, operation of the engine at excessively high speeds or oper-
ation of the vehicle at excessively high speeds.
Electronic Ignition (EI) SystemNBS004S4
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
Firing order: 1 - 2 - 3 - 4 - 5 - 6
The ignition timing is controlled by the ECM to maintain the best air-fuel ratio for every running condition of the
engine. The ignition timing data is stored in the ECM.
The ECM receives information such as the injection pulse width and camshaft position sensor (PHASE) sig-
nal. Computing this information, ignition signals are transmitted to the power transistor.
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
At idle
At low battery voltage
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
Battery
Battery voltage*
2
Knock sensor Engine knocking
Park/neutral position (PNP) switch Gear position
Wheel sensor
Vehicle speed*
1
EC-34
[VQ35DE]
ENGINE CONTROL SYSTEM
Revision: 2007 April2007 M35/M45
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.
Fuel Cut Control (At No Load and High Engine Speed)NBS004S5
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line.
SYSTEM DESCRIPTION
If the engine speed is above 1,400 rpm under no load (for example, the selector lever position is neutral and
engine speed is over 1,400 rpm) fuel will be cut off after some time. The exact time when the fuel is cut off var-
ies based on engine speed.
Fuel cut will be operated until the engine speed reaches 1,000 rpm, then fuel cut will be cancelled.
NOTE:
This function is different from deceleration control listed under Multiport Fuel Injection (MFI) System, EC-31,
"Multiport Fuel Injection (MFI) System" .
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 Vehicle speed*
EC-44
[VQ35DE]
EVAPORATIVE EMISSION SYSTEM
Revision: 2007 April2007 M35/M45
NOTE:
Do not start engine.
Improper installation of EVAP service port adapter to the EVAP service port may cause a leak.
WITH CONSULT-II
1. Attach the EVAP service port adapter securely to the EVAP service port.
2. Also attach the pressure pump and hose to the EVAP service port adapter.
3. Turn ignition switch ON.
4. Select the “EVAP SYSTEM CLOSE” of “WORK SUPPORT
MODE” with CONSULT-II.
5. Touch “START”. A bar graph (Pressure indicating display) will
appear on the screen.
6. Apply positive pressure to the EVAP system until the pressure
indicator reaches the middle of the bar graph.
7. Remove EVAP service port adapter and hose with pressure
pump.
8. Locate the leak using a leak detector. Refer to EC-40, "
EVAPO-
RATIVE EMISSION LINE DRAWING" .
WITHOUT CONSULT-II
1. Attach the EVAP service port adapter securely to the EVAP ser-
vice port.
2. Also attach the pressure pump with pressure gauge to the EVAP
service port adapter.
PEF838U
PEF917U
SEF200U
SEF462UA