2008 NISSAN LATIO battery

WARNING CHIME
DI-49
< SERVICE INFORMATION >
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B
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OK >> Replace BCM. Refer to BCS-18, "Removal and Installation of BCM".
NG >> Replace front door switch LH.
Key Switch Signal Inspection (Without Intelligent Key)INFOID:0000000001704529
1.CHECK FUSE
Check if the key switch and key lock solenoid 10A fuse [No. 14, located in the fuse block (J/B)] is blown.
OK or NG
OK >> GO TO 2.
NG >> Be sure to repair the cause of malfunction before installing new fuse. Refer to PG-3
.
2.CHECK BCM INPUT SIGNAL
With CONSULT-III
1. Select “BCM”.
2. With “DATA MONITOR” of “BUZZER”, confirm “KEY ON SW” when the key is operated.
Without CONSULT-III
Check voltage between BCM harness connector and ground.
OK or NG
OK >> Key switch signal is OK. Return to DI-46, "Trouble Diag-
nosis".
NG >> GO TO 3.
3.CHECK KEY SWITCH
1. Turn ignition switch OFF.
2. Disconnect key switch and key lock solenoid connector.
3. Check continuity between key switch and key lock solenoid ter-
minals 1 and 2.
OK or NG
OK >> GO TO 4.
NG >> Replace key switch and key lock solenoid.
4.CHECK KEY SWITCH CIRCUIT
1. Disconnect BCM connector.“KEY ON SW”
When key is inserted into ig-
nition key cylinder: ON
When key is removed from
ignition key cylinder: OFF
Te r m i n a l s
ConditionVoltag e
(Approx.) (+)
(−)
BCM
connectorTe r m i n a l
M18 37 GroundKey is inserted Battery voltage
Key is removed 0 V
PKIC0721E
Terminals Condition Continuity
12When key is inserted into ignition key cylinder Yes
When key is removed from ignition key cylinder No
WKIA5466E

DI-50
< SERVICE INFORMATION >
WARNING CHIME
2. Check continuity between BCM harness connector (A) and key
switch and key lock solenoid harness connector (B).
3. Check continuity between BCM harness connector (A) and
ground.
OK or NG
OK >> GO TO 5.
NG >> Repair harness or connector.
5.CHECK KEY SWITCH POWER SUPPLY CIRCUIT
Check voltage between key switch and key lock solenoid harness
connector and ground.
OK or NG
OK >> Replace BCM. Refer to BCS-18, "Removal and Installa-
tion of BCM".
NG >> Repair harness or connector.
Key Switch and Ignition Knob Switch Signal Inspection (With Intelligent Key, When Me-
chanical Key Is Used)
INFOID:0000000001704530
1.CHECK FUSE
Check if the key switch and ignition knob switch 10A fuse (No. 31, located in the fuse and fusible link box) is
blown.
OK or NG
OK >> GO TO 2.
NG >> Be sure to repair the cause of malfunction before installing new fuse. Refer to PG-3
.
2.CHECK BCM INPUT SIGNAL
With CONSULT-III
1. Select “BCM”.
2. With “DATA MONITOR” of “BUZZER”, confirm “KEY ON SW” when the key is operated.
Without CONSULT-III
AB
Continuity
Connector Terminal Connector Terminal
M18 37 M27 1 Yes
A
GroundContinuity
Connector Terminal
M18 37 No
PKIC0723E
Te r m i n a l s
Voltage
(Approx.) (+)
(−)
Key switch and key lock so-
lenoid connectorTe r m i n a l
M27 2 Ground Battery voltage
PKIC0724E
“KEY ON SW”
When key is inserted into
ignition key cylinder: ON
When key is removed from
ignition key cylinder: OFF

WARNING CHIME
DI-51
< SERVICE INFORMATION >
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Check voltage between BCM harness connector and ground.
OK or NG
OK >> Key switch and ignition knob switch signal is OK. Return
to DI-46, "
Trouble Diagnosis".
NG >> GO TO 3.
3.CHECK KEY SWITCH
1. Turn ignition switch OFF.
2. Disconnect key switch and ignition knob switch connector.
3. Check continuity between key switch and ignition knob switch
terminals 1 and 2.
OK or NG
OK >> GO TO 4.
NG >> Replace key switch and ignition knob switch.
4.CHECK KEY SWITCH CIRCUIT
1. Disconnect BCM connector.
2. Check continuity between BCM harness connector (A) and key
switch and ignition knob switch harness connector (B).
3. Check continuity between BCM harness connector (A) and
ground.
OK or NG
OK >> GO TO 5.
NG >> Repair harness or connector.
5.CHECK KEY SWITCH POWER SUPPLY CIRCUIT
Te r m i n a l s
ConditionVol tag e
(Approx.) (+)
(−)
BCM
connectorTe r m i n a l
M18 37 GroundKey is inserted Battery voltage
Key is removed 0
PKIC0721E
Terminals Condition Continuity
12When key is inserted into ignition key cylinder Yes
When key is removed from ignition key cylinder No
WKIA5466E
AB
Continuity
Connector Terminal Connector Terminal
M1837M73 1 Yes
A
GroundContinuity
Connector Terminal
M18 37 No
PKIC0723E

DI-52
< SERVICE INFORMATION >
WARNING CHIME
Check voltage between key switch and ignition knob switch harness
connector and ground.
OK or NG
OK >> Replace BCM. Refer to BCS-18, "Removal and Installa-
tion of BCM".
NG >> Repair harness or connector.
Lighting Switch Signal InspectionINFOID:0000000001704531
1.CHECK BCM INPUT SIGNAL
1. Select “BCM”.
2. With “DATA MONITOR” of “BUZZER”, confirm “LIGHT SW 1ST” when the lighting switch is operated.
OK or NG
OK >> Lighting switch signal is OK. Return to DI-46, "Trouble Diagnosis".
NG >> Check the lighting switch. Refer to LT-63, "
Combination Switch Inspection".
Parking Brake Switch Signal InspectionINFOID:0000000001815489
1.CHECK PARKING BRAKE SWITCH SIGNAL INPUT (COMBINATION METER)
1. Turn ignition switch ON.
2. Check voltage between combination meter harness connector
M24 terminal 10 and ground.
OK or NG
OK >> Replace combination meter. Refer to DI-20, "Removal and Installation".
NG >> GO TO 2.
2.CHECK PARKING BRAKE SWITCH CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect combination meter connector and parking brake switch connector.
Te r m i n a l s
Vo l ta g e
(Approx.) (+)
(−) Key switch and ignition
knob switch connector Te r m i n a l
M73 2 Ground Battery voltage
PKIC0724E
“LIGHT SW 1ST”
Lighting switch (1st position) : ON
Lighting switch (OFF) : OFF
Te r m i n a l s
ConditionVoltag e
(Approx.) (+)
(−) Combination
meter
connectorTe r m i n a l
M24 10 GroundParking brake released Battery voltage
Parking brake applied 0
AWMIA0066GB

EC-16
< SERVICE INFORMATION >
PRECAUTIONS
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000001702548
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 performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including incorrect removal and installation of the SRS, can lead to personal
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 har-
ness connectors.
Precaution for Procedure without Cowl Top CoverINFOID:0000000001702549
When performing the procedure after removing cowl top cover, cover
the lower end of windshield with urethane, etc.
On Board Diagnosis (OBD) System of Engine and A/T, CVTINFOID:0000000001702550
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 battery ground 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-lock-
ing type harness connector. For description and how to disconnect, refer to PG-65
.
• 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 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-17
< SERVICE INFORMATION >
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PrecautionINFOID:0000000001702551
•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 ignition switch OFF and then dis-
connect negative battery cable.
•Do not disassemble ECM.
•If battery cable is disconnected, the memory will return to the
initial ECM values.
The ECM will now start to self-control at its initial values.
Engine operation can vary slightly when the cable is discon-
nected. However, this is not an indication of a malfunction. 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 (1) as far as it will go as shown in the fig-
ure.
-ECM (2)
-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) volt-
age to develop in coil and condenser, thus resulting in dam-
age to ICs.
•Keep engine control system harness at least 10 cm (4 in) away
from adjacent harness, to prevent engine control system mal-
functions due to receiving external noise, degraded operation
of ICs, etc.
•Keep engine control system parts and harness dry.
SEF289H
PBIA9222J
PBIB2947E
PBIB0090E

ENGINE CONTROL SYSTEM
EC-23
< SERVICE INFORMATION >
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*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 (A/T and CVT models)
• High-load, high-speed operation

• During deceleration
• During high engine speed operation
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 (manifold) can then better reduce CO, HC and NOx emissions. This system uses air
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
EPS control unit
Power steering operation*
2
Heated oxygen sensor 2*1Density of oxygen in exhaust gas
Air conditioner switch
Air conditioner operation*
2
Wheel sensor
Vehicle speed*2
PBIB3020E

ENGINE CONTROL SYSTEM
EC-25
< SERVICE INFORMATION >
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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) SystemINFOID:0000000001702556
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 - 3 - 4 - 2
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
• 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)INFOID:0000000001702557
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line.
SYSTEM DESCRIPTION
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
Sensor Input Signal to ECM ECM function Actuator
Park/neutral position (PNP) switch Neutral position
Fuel cut control Fuel 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*