EC-12
Diagnosis Procedure .............................................865
P0462, P0463 FUEL LEVEL SENSOR ...........866
DTC Logic ............................................................ ..866
Diagnosis Procedure .............................................866
P0500 VSS .......................................................867
Description ........................................................... ..867
DTC Logic ..............................................................867
Diagnosis Procedure .............................................867
P0506 ISC SYSTEM ........................................869
Description ........................................................... ..869
DTC Logic ..............................................................869
Diagnosis Procedure .............................................869
P0507 ISC SYSTEM ........................................871
Description ........................................................... ..871
DTC Logic ..............................................................871
Diagnosis Procedure .............................................871
P050A, P050E COLD START CONTROL .......873
Description ........................................................... ..873
DTC Logic ..............................................................873
Diagnosis Procedure .............................................874
P0520 EOP SENSOR ......................................875
DTC Logic ............................................................ ..875
Diagnosis Procedure .............................................875
Component Inspection ...........................................877
P0524 ENGINE OIL PRESSURE ....................878
DTC Logic ............................................................ ..878
Diagnosis Procedure .............................................879
Component Inspection ...........................................880
P0603 ECM POWER SUPPLY ........................881
DTC Logic ............................................................ ..881
Diagnosis Procedure .............................................881
P0605 ECM ......................................................883
DTC Logic ............................................................ ..883
Diagnosis Procedure .............................................883
P0607 ECM ......................................................884
DTC Logic ............................................................ ..884
Diagnosis Procedure .............................................884
P0643 SENSOR POWER SUPPLY .................885
Description ........................................................... ..885
DTC Logic ..............................................................885
Diagnosis Procedure .............................................885
P0850 PNP SWITCH .......................................887
Description ........................................................... ..887
DTC Logic ..............................................................887
Component Function Check ..................................888
Diagnosis Procedure .............................................888
P1148, P1168 CLOSED LOOP CONTROL .....890
DTC Logic ............................................................ ..890
P1212 TCS COMMUNICATION LINE ..............891
Description ........................................................... .891
DTC Logic .............................................................891
Diagnosis Procedure .............................................891
P1217 ENGINE OVER TEMPERATURE .........892
DTC Logic ............................................................ .892
Component Function Check .................................892
Diagnosis Procedure .............................................893
P1225 TP SENSOR ..........................................895
DTC Logic ............................................................ .895
Diagnosis Procedure .............................................895
P1226 TP SENSOR ..........................................896
DTC Logic ............................................................ .896
Diagnosis Procedure .............................................896
P1550 BATTERY CURRENT SENSOR ...........897
DTC Logic ............................................................ .897
Diagnosis Procedure .............................................897
Component Inspection ..........................................898
P1551, P1552 BATTERY CURRENT SEN-
SOR ................................................................ ..
899
DTC Logic ............................................................ .899
Diagnosis Procedure .............................................899
Component Inspection ..........................................900
P1553 BATTERY CURRENT SENSOR ...........901
DTC Logic ............................................................ .901
Diagnosis Procedure .............................................901
Component Inspection ..........................................902
P1554 BATTERY CURRENT SENSOR ...........903
DTC Logic ............................................................ .903
Component Function Check .................................903
Diagnosis Procedure .............................................903
Component Inspection ..........................................904
P1556, P1557 BATTERY TEMPERATURE
SENSOR ......................................................... ..
906
DTC Logic ............................................................ .906
Diagnosis Procedure .............................................906
Component Inspection (Battery Temperature
Sensor) ................................................................ .
907
P1564 ASCD STEERING SWITCH ..................908
DTC Logic ............................................................ .908
Diagnosis Procedure .............................................908
Component Inspection ..........................................910
P1572 ASCD BRAKE SWITCH ........................911
Description ........................................................... .911
DTC Logic .............................................................911
Component Function Check .................................912
Diagnosis Procedure .............................................913
Component Inspection (Brake Pedal Position
Switch) ................................................................. .
916
Component Inspection (Stop Lamp Switch) ..........916
Component Inspection (Stop Lamp Relay) ...........917
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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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EC-16
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PRECAUTIONS
• Be sure to connect rubber tubes properly afte
r 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 info rmation (repairs completed) from the ECM and
TCM (Transmission control module) before returning the vehicle to the customer.
General PrecautionsINFOID:0000000009462050
•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 bat-
tery 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 ig nition switch OFF and then dis-
connect battery ground 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 slight ly when the terminal is dis-
connected. However, this is no t an indication of a malfunc-
tion. Do not replace parts b ecause 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 or disconnect ing 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) volt-
age to develop in coil and co ndenser, thus resulting in dam-
age to ICs.
• Keep engine control system harness at least 10 cm (4 in) away
from adjacent harness, to preven t engine control system mal-
functions due to receiving exter nal noise, degraded operation
of ICs, etc.
• Keep engine control system parts and harness dry.
• Before replacing ECM, perform ECM Terminals and Reference
Value inspection and make sure ECM functions properly.
Refer to EC-88, "Reference Value"
.
• Handle mass air flow sensor carefully to avoid damage.
• Do not clean mass air flow senso r with any type of detergent.
• Do not disassemble electric throttle control actuator.
• Even a slight leak in the ai r intake system can cause serious
incidents.
• Do not shock or jar the camshaft position sensor (PHASE),
crankshaft position sensor (POS).
SEF289H
PBIA9222J
PBIB0090E
MEF040D
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COMPONENT PARTSEC-21
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SYSTEM DESCRIPTION
COMPONENT PARTS
Component Parts LocationINFOID:0000000009462053
ENGINE ROOM COMPARTMENT
ALBIA0804ZZ
No. Component Function
EVAP canister purge volume control solenoid valve EC-34, "EVAP Canister Purge Volume Control Solenoid
Va l v e "
Transmission range switch• The transmission range switch is installed to upper part
of transaxle case.
• ECM detects the selector lever position because the continuity of the transmission range switch line (the
ON) exists.
ECM EC-25, "ECM"
Refrigerant pressure sensorEC-36, "Refrigerant Pressure Sensor"
Battery current sensor
(with battery temperature sensor) EC-35, "Battery Current Se
nsor (With Battery Tempera-
ture Sensor)"
IPDM E/R • IPDM E/R control the internal relays and the actuators.
-Refer to PCS-6, "RELAY CONTROL SYSTEM : Sys-tem Description".
• When CAN communication with ECM is impossible,
IPDM E/R performs fail-safe control.
-Refer to PCS-19, "Fail Safe"
.
Mass air flow sensor
(with intake air temperature sensor) EC-27, "Mass Air Flow Sensor (With Intake Air Tempera-
ture Sensor)"
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EC-26
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COMPONENT PARTS
THROTTLE CONTROL MOTOR RELAY
Power supply for the throttle control motor is provided to
the ECM via throttle control motor relay. The throttle
control motor relay is ON/OFF controlled by the ECM. When the ignition switch is turned ON, the ECM sends
an ON signal to throttle control motor relay and battery voltage is provided to the ECM. When the ignition
switch is turned OFF, the ECM sends an OFF signal to throttle control motor relay and battery voltage is not
provided to the ECM.
THROTTLE CONTROL MOTOR
The throttle control motor is operated by the ECM and it opens and closes the throttle valve.
The current opening angle of the throttle valve is detected by the throttle position sensor and it provides feed-
back to the ECM to control the throttle control mo tor to make the throttle valve opening angle properly in
response to driving condition.
THROTTLE POSITION SENSOR
The throttle position sensor responds to the throttle valve movement.
The throttle position sensor has two sensors. These sensors are a
kind of potentiometers which transform the throttle valve position into
output voltage, and emit the voltage signal to the ECM. In addition,
these sensors detect the opening and closing speed of the throttle
valve and feed the voltage signals to the ECM. The ECM judges the
current opening angle of the throttle valve from these signals and the
ECM controls the throttle control motor to make the throttle valve
opening angle properly in response to driving condition.
Ignition Coil With Power TransistorINFOID:0000000009462057
The ignition signal from the ECM is sent to and amplified by the
power transistor. The power transistor turns ON and OFF the ignition
coil primary circuit. This ON/OFF operation induces the proper high
voltage in the coil secondary circuit.
Fuel InjectorINFOID:0000000009462058
The fuel injector is a small, precise solenoid valve. When the ECM
supplies a ground to the fuel injector circuit, the coil in the fuel injec-
tor is energized. The energized coil pulls the ball valve back and
allows fuel to flow through the fuel injector into the intake manifold.
The amount of fuel injected depends upon the injection pulse dura-
tion. Pulse duration is the length of time the fuel injector remains
open. The ECM controls the injection pulse duration based on
engine fuel needs.
Fuel Level Sensor Unit and Fuel PumpINFOID:0000000009462059
FUEL PUMP
PBIB0145E
JPBIA4613ZZ
JPBIA5845ZZ
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COMPONENT PARTSEC-27
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The ECM activates the fuel pump for 1 second after the ignition
switch is turned ON to improve engine start ability. If the ECM
receives a engine speed signal from the camshaft position sensor
(PHASE), it knows that the engine is rotating, and causes the pump
to operate. If the engine speed signal is not received when the igni-
tion switch is ON, the engine stalls. The ECM stops pump operation
and prevents battery discharging, thereby improving safety. The
ECM does not directly drive the fuel pump. It sends the control signal
to the fuel pump control module, which in turn controls the fuel
pump.
FUEL LEVEL SENSOR
The fuel level sensor is mounted in the fuel level sensor unit.
The sensor detects a fuel level in the fuel tank and tr ansmits a signal to the combination meter. The combina-
tion meter sends the fuel level sensor signal to the ECM via the CAN communication line.
It consists of two parts, one is mechanical float and the ot her is variable resistor. Fuel level sensor output volt-
age changes depending on the movement of the fuel mechanical float.
Fuel Tank Temperature SensorINFOID:0000000009462060
The fuel tank temperature sensor is used to detect the fuel tempera-
ture inside the fuel tank. The sensor modifies a voltage signal from
the ECM. The modified signal returns to the ECM as the fuel temper-
ature 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.
*: These data are reference values and are measured between ECM terminals.
Mass Air Flow Sensor (With Intake Air Temperature Sensor)INFOID:0000000009462061
MASS AIR FLOW SENSOR
JPBIA5842ZZ
Condition Fuel pump operation
Ignition switch is turned to ON. Operates for 1 second.
Engine running and cranking Operates.
When engine is stopped Stops in 1.5 seconds.
Except as shown above Sto ps .
SEF012P
Fluid temperature
[° C ( °F)] Voltage* (V) Resistance (k
Ω)
20 (68) 3.5 2.3 - 2.7
50 (122) 2.2 0.79 - 0.90
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COMPONENT PARTSEC-35
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EVAP Canister Vent Control ValveINFOID:0000000009462080
The EVAP canister vent control valve is located on the EVAP canis-
ter and is used to seal the canister vent.
This solenoid valve responds to signals from the ECM. When the
ECM sends an ON signal, the coil in the solenoid valve is energized.
A plunger will then move to seal the canister vent. The ability to seal
the vent is necessary for the on board diagnosis of other evaporative
emission control system components.
This solenoid valve is used only for diagnosis, and usually remains
opened.
When the vent is closed, under normal purge conditions, the evapo-
rative emission control system is depressurized and allows “EVAP
Control System” diagnosis.
EVAP Control System Pressure SensorINFOID:0000000009462081
The EVAP control system pressure sensor detects pressure in the
purge line. The sensor output voltage to the ECM increases as pres-
sure increases.
Battery Current Sensor (With Battery Temperature Sensor)INFOID:0000000009462082
OUTLINE
The power generation voltage variable control enables fuel con-
sumption to be decreased by reducing the engine load which is
caused by the power generation of the generator.
Based on sensor signals, ECM judges whether or not the power
generation voltage variable contro l is performed. When performing
the power generation voltage variable control, ECM calculates the
target power generation voltage based on the sensor signal. And
ECM sends the calculated value as the power generation command
value to IPDM E/R. For the details of the power generation voltage
variable control, refer to CHG-10, "System Description"
.
CAUTION:
Never connect the electrical co mponent or the ground wire
directly to the battery terminal. The connection cau ses the malfunction of the power generation volt-
age variable control, and then the battery discharge may occur.
BATTERY CURRENT SENSOR
The battery current sensor is installed to the battery negative cable. The sensor measures the charging/dis-
charging current of the battery.
BATTERY TEMPERATURE SENSOR
PBIB1263E
PBIB3370E
JPBIA3262ZZ
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EC-36
< SYSTEM DESCRIPTION >[QR25DE]
COMPONENT PARTS
Battery temperature sensor is int
egrated in battery current sensor.
The sensor measures temperature around the battery.
The electrical resistance of the t hermistor decreases as temperature
increases.
*: These data are reference values and are measured between battery temperature
sensor signal terminal and sensor ground.
Malfunction Indicator lamp (MIL)INFOID:0000000009462083
The Malfunction Indicator lamp (MIL) is located on the combination
meter.
The MIL will illuminate when the ignition switch is turned ON without
the engine running. This is a bulb check.
When the engine is started, the MI L should turn OFF. If the MIL
remains illuminated, the on board diagnostic system has detected an
engine system malfunction.
For details, refer to EC-74, "DIAGNOSIS DESCRIPTION : Malfunc-
tion Indicator Lamp (MIL)".
Oil Pressure Warning LampINFOID:0000000009462084
Oil pressure warning lamp is located on the combination meter.
It indicates the low pressure of the engine oil and the malfunction of
the engine oil pressure system.
Combination meter turns the oil pressure warning lamp ON/OFF
according to the oil pressure warning lamp signal received from
ECM via CAN communication.
For details, refer to EC-55, "ENGINE PROTECTION CONTROL AT
LOW ENGINE OIL PRESSURE : System Description".
Refrigerant Pressure SensorINFOID:0000000009462085
The refrigerant pressure sensor is installed at the c ondenser of the air conditioner system. The sensor uses an
electrostatic volume pressure transducer to convert refrigerant pressure to voltage. The voltage signal is sent
to ECM, and ECM controls cooling fan system.
Stop Lamp Switch & Brake Pedal Position SwitchINFOID:0000000009462086
Stop lamp switch and brake pedal position switch are installed to brake pedal bracket.
ECM detects the state of the brake pedal by those two types of input (ON/OFF signal).
Temperature [°C ( °F)]
Vo l ta g e* (V) Resistance (k
Ω)
25 (77) 3.333 1.9 - 2.1
90 (194) 0.969 0.222 - 0.258
SEF012P
JSBIA1315ZZ
PBIA8559J
PBIB2657E
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