PRECAUTIONSEC-15
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PRECAUTION
PRECAUTIONS
Precaution for Supplemental
Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000009951805
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty of injury to the driver and front passenger for certain
types of collision. Information necessary to service t he system safely is included in the SR and SB section of
this Service Manual.
WARNING:
• To avoid rendering the SRS inoper ative, 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 performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipm ent on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Un it or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or el ectric power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery and wait at least three mi nutes before performing any service.
Precaution for Procedure without Cowl Top CoverINFOID:0000000009462048
When performing the procedure after removing cowl top cover, cover
the lower end of windshield with urethane, etc to prevent damage to
windshield.
On Board Diagnostic (OBD) S ystem of Engine and CVTINFOID:0000000009462049
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 di sconnect the negative battery cable before any repair
or inspection work. The open/short circuit of re lated switches, sensors, solenoid valves, etc. will
cause the MIL to light up.
• Be sure to connect and lock the connectors secure ly 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-lock-
ing type harness connector. For descripti on and how to disconnect, refer to PG-65, "Description"
.
• 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 li ght up due to the short circuit.
PIIB3706J
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COMPONENT PARTSEC-23
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EXHAUST COMPARTMENT
BODY COMPARTMENT
Intake valve timing intermediate lock control solenoid valve
EC-30, "Intake Valve Timing Intermediate Lock Control So-lenoid Valve"
Intake valve timing control solenoid valve
EC-30, "Intake Valve Timing Control Solenoid Valve"
Exhaust valve timing control solenoid valveEC-31, "Exhaust Valve Timing Control Solenoid Valve"
Ignition coil (with power transistor)EC-26, "Ignition Coil With Power Transistor"
Engine coolant temperature sensorEC-28, "Engine Coolant Temperature Sensor"
Intake manifold tuning valveEC-31, "Intake Manifold Tuning Valve"
Intake manifold runner control valve position sensor
EC-31, "Intake Manifold Runner Control Valve"
Intake manifold runner control valve actuator
No. Component Function
To engine assembly
JPBIA5841ZZ
No. Component Function
Air fuel ratio (A/F) sensor 1 EC-32, "Air Fuel Ratio (A/F) Sensor 1"
Heated oxygen sensor 2EC-32, "Heated Oxygen Sensor 2"
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EC-30
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COMPONENT PARTS
ECM receives the signals as shown in the figure.
Intake Valve Timing Control Solenoid ValveINFOID:0000000009462066
Intake valve timing control solenoid valve is activated by ON/OFF
pulse duty (ratio) signals from the ECM.
The intake valve timing control solenoid valve changes the oil
amount and direction of flow through intake valve timing control unit
or stops oil flow.
The longer pulse width advances valve angle.
The shorter pulse width retards valve angle.
When ON and OFF pulse widths become equal, the solenoid valve
stops oil pressure flow to fix the intake valve angle at the control
position.
Intake Valve Timing Intermediate Lock Control Solenoid ValveINFOID:0000000009462067
Intake valve timing intermediate lock control solenoid valve is acti-
vated by ON/OFF signals from the ECM.
The intake valve timing intermediate lock control solenoid valve
opens/closes the path of oil pressure acting on the lock key in the
camshaft sprocket (INT).
• When the solenoid valve becomes ON, oil pressure to the lock key
is trained to perform intermediate lock.
• When the solenoid valve becomes OFF, oil pressure is acted on the lock key to release the intermediate lock.
Exhaust Valve Timing Control Position SensorINFOID:0000000009462068
Exhaust valve timing control position sensor detects the protrusion of
the signal plate installed to the exhaust camshaft front end.
This sensor signal is used for sensing a position of the exhaust cam-
shaft.
The sensor consists of a permanent magnet and Hall IC.
When engine is running, the high and low parts of the teeth cause
the gap with the sensor to change.
The changing gap causes the magnetic field near the sensor to
change.
Due to the changing magnetic field, the voltage from the sensor
changes.
JMBIA0714GB
PBIB1842E
PBIB1842E
JPBIA5847ZZ
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COMPONENT PARTSEC-33
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Knock SensorINFOID:0000000009462074
The knock sensor is attached to t
he cylinder block. It senses engine
knocking using a piezoelectric el ement. A knocking vibration from
the cylinder block is sensed as vibrational pressure. This pressure is
converted into a voltage signal and sent to the ECM.
Engine Oil Pressure SensorINFOID:0000000009462075
The engine oil pressure (EOP) sens or is detects engine oil pressure
and transmits a voltage signal to the ECM.
Engine Oil Temperature SensorINFOID:0000000009462076
The engine oil temperature sensor is used to detect the engine oil
temperature. The sensor modifies a voltage signal from the ECM.
The modified signal returns to the ECM as the engine oil tempera-
ture input. The sensor uses a ther mistor which is sensitive to the
change in temperature. The electrical resistance of the thermistor
decreases as temperature increases.
Engine speed Heated oxygen sensor 2 heater
Above 3,600 rpm OFF
Below 3,600 rpm after the following conditions are met.
• Engine: After warming up
• Keeping the engine speed between 3,500 and 4,000 rpm for 1
minute and at idle for 1 minute under no load ON
JSBIA0284ZZ
JSBIA0292ZZ
JPBIA5280ZZ
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EC-42
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SYSTEM
Fail Safe Pattern
Fail Safe List
× :Applicable —: Not applicable
Fail safe mode Vehicle behavior
Traveling con-
trol mode Accelerator an-
gle variation
control ECM controls the accelerator pedal depression speed to make it slower than actual speed. This
causes a drop in accelerating performance and encourages the driver to repair malfunction.
NOTE:
ECM does not control the accelerator pedal releasing speed.
Engine output
control ECM reduces the engine output, according to the rise in engine speed. This reduces the vehicle
speed to encourage the driver to repair malfunction.
Device fix mode • This mode fixes the IVT control solenoid valve and the EVT control solenoid valve in the refer-
ence position.
• The intake manifold runner control valve motor is turned OFF (intake manifold runner control valve opens).
Pattern Fail safe mode
A Traveling control mode Accelerator angle variation control
B Engine output control
C Device fix mode
DTC No. Detected items Vehicle behavior
Pattern Others
ABC
P0011 Intake valve timing control ——×ECM activates the IVT intermediate lock control solenoid
valve to bring the cam sprocket into an intermediate lock con-
dition.
P0014
P0078 Exhaust valve timing control
——× —
P0101
P0102
P0103 Mass air flow sensor circuit
××× —
P0122
P0123
P0222
P0223
P2135 Throttle position sensor
———The ECM controls the electric throttle control actuator in reg-
ulating the throttle opening in order for the idle position to be
within +10 degrees.
The ECM regulates the opening speed of the throttle valve to
be slower than the normal condition.
So, the acceleration will be poor.
P0171
P0172 Fuel injection system
×—— —
P0197
P0198 Engine oil temperature sensor
———Exhaust valve timing control does not function.
P0300
P0301
P0302
P0303
P0304 Misfire
×—— —
P0500 Vehicle speed sensor ×—— —
P050A Cold start control ×—— —
P0524 Engine oil pressure
———• ECM illuminates oil pressure warning lamp on the combina-
tion meter.
• Engine speed will not rise more than 4,000rpm due to the
fuel cut.
• Fail-safe is canceled when ignition switch OFF → ON.
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SYSTEMEC-43
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MULTIPORT FUEL INJECTION SYSTEM
MULTIPORT FUEL INJECTION SYSTEM : S
ystem Description (with automatic air
P052A
P052B Intake valve timing intermedi-
ate lock control ——
× —
P0603 ECM power supply circuit — ×——
P0605 ECM — ×——
P0643 Sensor power supply ———ECM stops the electric throttle control actuator control, throttle
valve is maintained at a fixed opening (approx. 5 degrees) by
the return spring.
P1078 Exhaust valve timing control position sensor circuit ×
— × —
P1805 Brake switch
———ECM controls the electric throttle control actuator by regulat-
ing the throttle opening to a small range.
Therefore, acceleration will be poor.
Vehicle condition Driving condition
When engine is idling Normal When accelerating Poor acceleration
P2004 Intake manifold runner control valve —
×× —
P2100
P2103 Throttle contro
l motor relay
——— ECM stops the electric throttle control actuator control, throttle
valve is maintained at a fixed opening (approx. 5 degrees) by
the return spring.
P2101 Electric throttle control func- tion ——— ECM stops the electric throttle control actuator control, throttle
valve is maintained at a fixed opening (approx. 5 degrees) by
the return spring.
P2118 Throttle control motor ———ECM stops the electric throttle control actuator control, throttle
valve is maintained at a fixed opening (approx. 5 degrees) by
the return spring.
P2119 Electric thro ttle control actua-
tor —
×——
P2122
P2123
P2127
P2128
P2138 Accelerator pedal position
sensor
———The ECM controls the electric throttle control actuator in reg-
ulating the throttle opening in order for the idle position to be
within +10 degrees.
The ECM regulates the opening speed of the throttle valve to
be slower than the normal condition.
So, the acceleration will be poor.
DTC
No. Detected items Vehicle behavior
Pattern Others
ABC
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EC-50
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SYSTEM
System Description
This mechanism hydraulically controls cam phases c
ontinuously with the fixed operating angle of the intake
valve.
The ECM receives signals such as crankshaft posit ion, camshaft position, engine speed, and engine coolant
temperature. Then, the ECM sends ON/OFF pulse duty si gnals to the intake valve timing (IVT) control sole-
noid valve depending on driving status. This makes it po ssible to control the shut/open timing of the intake
valve to increase engine torque in low/mid speed range and output in high-speed range.
INTAKE VALVE TIMING INTERMEDIATE LOCK CONTROL
System Diagram
System Description
JPBIA6316GB
JPBIA5973GB
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SYSTEMEC-51
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The intake valve timing intermediate lock control improv
es the cleaning ability of exhaust gas at cold starting
by fixing the camshaft sprocket (INT) with two lock keys and bringing the cam phase into intermediate phase.
Cam phase is fixed at the intermediate phase by two lock keys in the camshaft sprocket (INT). Lock key 1 con-
trols retard position and lock key 2 controls advance position.
ECM controls the intermediate phase lock by opening/clos ing the intake valve timing intermediate lock control
solenoid valve to control oil pressure acti ng on the lock key and locking/unlocking the lock key.
Lock/Unlock Activation
When ECM activates the intake valve timing intermediate lock control solenoid valve, oil pressure generated in
the oil pump is drained through the oil pressure path in t he control valve. Since oil pressure is not acted on the
lock key, the lock key position is fixed by the spri ng tension and the cam phase is fixed at the intermediate
phase.
When ECM deactivates the intake valve timing intermediate lock control solenoid valve, unlocking oil pressure
acts on each lock key. Lock key 1 is not released because it is under load due to sprocket rotational force. For
this reason, lock key 2 is released first by being pushed up by unlocking oil pressure. When lock key 2 is
released, some clearance is formed between lock key 1 and the rotor due to sprocket rotational force and
return spring force. Accordingly, lock key 1 is pushed up by unlocking oil pressure and the intermediated
phase lock is released.
When stopping the engine
When the ignition switch is turned from idle state to OFF, ECM receives an ignition switch signal from BCM via
CAN communication and activates the intake valve timing intermediate lock control solenoid valve and drains
oil pressure acting on the lock key before activating the intake valve timing control solenoid valve and operat-
ing the cam phase toward the advance position.
The cam phase is fixed by the lock key when shifting to the intermediated phase and ECM performs Lock
judgment to stop the engine.
When starting the engine
JPBIA6317GB
JPBIA5970GB
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