DI-104
COMPASS
Revision: 2007 April2007 M35/M45
Zone Variation Setting ProcedureNKS004F5
NOTE:
The zone setting is factory preset (“default” setting) to zone 8.
1. Press and hold the compass switch for 3 – 9 seconds.
2. The current zone setting appears on the compass display.
3. Find the current geographical location number in the Zone Varia-
tion Chart.
4. Select the new zone number. (Press the compass switch until
the new zone number appears on the compass display.)
5. After select the new zone number, the compass display will
automatically shows a direction within a few seconds.
6. Preform the following Calibration Procedure for more accurate
indications.
Calibration ProcedureNKS004F6
NOTE:
The compass calibrates itself under normal driving conditions. However, occasional circumstances may cause
the compass to operate inaccurately. Example: Driving from rural (wide open) areas to crowded city areas, or
if an aftermarket (i.e., non original equipment) antenna with a magnetic base is attached to the vehicle. Cali-
brate the mirror compass if the display shows only one direction or a limited number of directions.
NOTE:
If “magnetic hats” are used in the dealership for vehicle identification, remove the hat from the vehicle
before performing the following steps. Do NOT put the hat back on the vehicle after the procedure is com-
pleted.
Drive the vehicle to an open level area; away from large metallic objects, structures, and overhead power
lines.
Turn off “non-essential” electrical accessories (rear window defrost, heater/air conditioning, wipers) and
close the doors.
1. Verify the correct compass zone setting for the geographical location. Refer to DI-104, "
Zone Variation
Setting Procedure" .
2. Press and hold the compass switch for more than 9 seconds.
3. “C” is displayed on the compass display, when calibration starts.
4. Drive slowly [less than 8 km/h (5 mph)] in a circle until the “C / CAL” is replaced with primary headings (N,
NE, E, SE, S, SW, W, or NW).
NOTE:
This will require driving at least 2 complete 360 degree circles; 3 complete circles may be required.
5. The compass calibration procedure is now complete. The compass should operate normally.
NOTE:
If at any time the compass continually displays the incorrect direction or the reading is erratic or locked,
repeat the calibration procedure.
SEL168Y
EC-1
ENGINE CONTROL SYSTEM
B ENGINE
CONTENTS
C
D
E
F
G
H
I
J
K
L
M
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
ENGINE CONTROL SYSTEM
EC-31
[VQ35DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2007 April2007 M35/M45
Multiport Fuel Injection (MFI) SystemNBS004S3
INPUT/OUTPUT SIGNAL CHART
*1: This sensor is not used to control the engine system under normal conditions.
*2: This signal is sent to the ECM through CAN communication line.
*3: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
The amount of fuel injected from the fuel injector is determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). The amount of fuel injected is a program value in the
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from the crankshaft position sensor (POS), camshaft position
sensor (PHASE) and the mass air flow sensor.
VARIOUS FUEL INJECTION INCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compensated to improve engine performance under various operat-
ing conditions as listed below.
During warm-up
When starting the engine
During acceleration
Hot-engine operation
When selector lever is changed from N to D
High-load, high-speed operation
During deceleration
During high engine speed operation
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Engine speed*
3
Piston position
Fuel injection
& mixture ratio
controlFuel injector Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Park/neutral position (PNP) switch Gear position
Battery
Battery voltage*
3
Knock sensor Engine knocking condition
Power steering pressure sensor Power steering operation
Heated oxygen sensor 2*
1Density of oxygen in exhaust gas
ABS actuator and electric unit (control unit)
VDC/TCS operation command*
2
Air conditioner switch
Air conditioner operation*2
Wheel sensor
Vehicle speed*2
EC-32
[VQ35DE]
ENGINE CONTROL SYSTEM
Revision: 2007 April2007 M35/M45
MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)
The mixture ratio feedback system provides the best air-fuel mixture ratio for driveability and emission control.
The three way catalyst 1 can then better reduce CO, HC and NOx emissions. This system uses A/F sensor 1
in the exhaust manifold to monitor whether the engine operation is rich or lean. The ECM adjusts the injection
pulse width according to the sensor voltage signal. For more information about A/F sensor 1, refer to EC-244,
"DTC P0131, P0151 A/F SENSOR 1" . This maintains the mixture ratio within the range of stoichiometric (ideal
air-fuel mixture).
This stage is referred to as the closed loop control condition.
Heated oxygen sensor 2 is located downstream of the three way catalyst 1. Even if the switching characteris-
tics of A/F sensor 1 shift, the air-fuel ratio is controlled to stoichiometric by the signal from heated oxygen sen-
sor 2.
Open Loop Control
The open loop system condition refers to when the ECM detects any of the following conditions. Feedback
control stops in order to maintain stabilized fuel combustion.
Deceleration and acceleration
High-load, high-speed operation
Malfunction of A/F sensor 1 or its circuit
Insufficient activation of A/F sensor 1 at low engine coolant temperature
High engine coolant temperature
During warm-up
After shifting from N to D
When starting the engine
MIXTURE RATIO SELF-LEARNING CONTROL
The mixture ratio feedback control system monitors the mixture ratio signal transmitted from A/F sensor 1.
This feedback signal is then sent to the ECM. The ECM controls the basic mixture ratio as close to the theoret-
ical mixture ratio as possible. However, the basic mixture ratio is not necessarily controlled as originally
designed. Both manufacturing differences (i.e., mass air flow sensor hot wire) and characteristic changes dur-
ing operation (i.e., fuel injector clogging) directly affect mixture ratio.
Accordingly, the difference between the basic and theoretical mixture ratios is monitored in this system. This is
then computed in terms of “injection pulse duration” to automatically compensate for the difference between
the two ratios.
“Fuel trim” refers to the feedback compensation value compared against the basic injection duration. Fuel trim
includes short term fuel trim and long term fuel trim.
“Short term fuel trim” is the short-term fuel compensation used to maintain the mixture ratio at its theoretical
value. The signal from A/F sensor 1 indicates whether the mixture ratio is RICH or LEAN compared to the the-
oretical value. The signal then triggers a reduction in fuel volume if the mixture ratio is rich, and an increase in
fuel volume if it is lean.
“Long term fuel trim” is overall fuel compensation carried out long-term to compensate for continual deviation
of the short term fuel trim from the central value. Such deviation will occur due to individual engine differences,
wear over time and changes in the usage environment.
PBIB3020E
ENGINE CONTROL SYSTEM
EC-33
[VQ35DE]
C
D
E
F
G
H
I
J
K
L
MA
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
AIR CONDITIONING CUT CONTROL
EC-35
[VQ35DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2007 April2007 M35/M45
AIR CONDITIONING CUT CONTROLPFP:23710
Input/Output Signal ChartNBS004S6
*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 DescriptionNBS004S7
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.
Sensor Input Signal to ECM ECM function Actuator
Air conditioner switch
Air conditioner ON signal*
1
Air conditioner
cut controlAir conditioner relay Accelerator pedal position sensor Accelerator pedal position
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
Vehicle speed*
1
POSITIVE CRANKCASE VENTILATION
EC-51
[VQ35DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2007 April2007 M35/M45
POSITIVE CRANKCASE VENTILATIONPFP:11810
DescriptionNBS004SI
SYSTEM DESCRIPTION
This system returns blow-by gas to the intake manifold.
The positive crankcase ventilation (PCV) valve is provided to conduct crankcase blow-by gas to the intake
manifold.
During partial throttle operation of the engine, the intake manifold sucks the blow-by gas through the PCV
valve.
Normally, the capacity of the valve is sufficient to handle any blow-by and a small amount of ventilating air.
The ventilating air is then drawn from the air inlet tubes into the crankcase. In this process the air passes
through the hose connecting air inlet tubes to rocker cover.
Under full-throttle condition, the manifold vacuum is insufficient to draw the blow-by flow through the valve.
The flow goes through the hose connection in the reverse direction.
On vehicles with an excessively high blow-by, the valve does not
meet the requirement. This is because some of the flow will go
through the hose connection to the air inlet tubes under all condi-
tions.
Component InspectionNBS004SJ
PCV (POSITIVE CRANKCASE VENTILATION) VALVE
With engine running at idle, remove PCV valve from rocker cover. A
properly working valve makes a hissing noise as air passes through
it. A strong vacuum should be felt immediately when a finger is
placed over valve inlet.
SEC921C
PBIB1588E
PBIB1589E