2009 NISSAN LATIO coolant temperature

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Fuel filler cap adapter
i.e.: (MLR-8382) Checks fuel tank vacuum relief valve opening
pressure
Socket wrench Removes and installs engine coolant temperature sensor
Oxygen sensor thread
cleaner
i.e.: (J-43897-18)
(J-43897-12) Reconditions the exhaust system threads before
installing a new oxygen sensor. Use with anti-
seize lubricant shown below.
a: 18 mm diameter with pitch 1.5 mm for Zirco-
nia Oxygen Sensor
b: 12 mm diameter with pitch 1.25 mm for Tita-
nia Oxygen Sensor
Anti-seize lubricant
i.e.: (Permatex TM

133AR or equivalent
meeting MIL specifica-
tion MIL-A-907) Lubricates oxygen sensor thread cleaning tool
when reconditioning exhaust system threads.
Tool name
(Kent-Moore No.) DescriptionS-NT705
AEM488
S-NT779

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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). T he amount of fuel injected is a program value in the
ECM memory. The program value is preset by engi ne operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from t he 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 compens ated 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) Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed*3
Piston position
Fuel injection
& mixture ratio
control Fuel 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* 1
Density of oxygen in exhaust gas
Air conditioner switch Air conditioner operation*2
ABS actuator and electric unit (control unit) Vehicle speed*2
Combination meter

EC-520< SERVICE INFOMATION >
[MR TYPE 1]
ENGINE CONTROL SYSTEM
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 r educe CO, HC and NOx emissions. This system uses air
fuel ratio (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 t he sensor voltage signal. For more information about air
fuel ratio (A/F) sensor 1, refer to EC-698 . 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 th ree way catalyst (manifold). Even if the switching
characteristics of air fuel ratio (A/F) sensor 1 shift, the air/fuel ratio is controlled to stoichiometric by the signal
from heated oxygen sensor 2.
Open Loop Control
The open loop system condition refers to when the EC M 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 air fuel ratio (A/F) sensor 1 or its circuit
• Insufficient activation of air fuel ratio (A /F) sensor 1 at low engine coolant temperature
• High engine coolant temperature
• During warm-up
• After shifting from N to D (A/T and CVT models)
• When starting the engine
MIXTURE RATIO SELF-LEARNING CONTROL
The mixture ratio feedback control system monitors the mixt ure ratio signal transmitted from air fuel ratio (A/F)
sensor 1. This feedback signal is then sent to the ECM. The ECM controls the basic mixture ratio as close to
the theoretical mixture ratio as possible. However, the bas ic mixture ratio is not necessarily controlled as orig-
inally designed. Both manufacturing differences (i.e., mass air flow sensor hot wire) and characteristic
changes during 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 co mpared 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 compensati on used to maintain the mixture ratio at its theoretical
value. The signal from air fuel ratio (A/F) sensor 1 i ndicates whether the mixture ratio is RICH or LEAN com-
pared to the theoretical value. The signal then triggers a r eduction 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 carri ed out long-term to compensate for continual deviation
of the short term fuel trim from t he central value. Such deviation will occur due to individual engine differences,
wear over time and changes in the usage environment.
FUEL INJECTION TIMING
Two types of systems are used.
Sequential Multiport Fuel Injection System
Fuel is injected into each cylinder during each engine cycl e 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 four cylinders twice each engine cycle. In other words, pulse signals of
the same width are simultaneously transmitted from the ECM.
The four fuel injectors will then receive the signals two times for each engine cycle. SEF337W

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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) System INFOID:0000000004537021
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 injecti on pulse width and camshaft position sensor (PHASE) sig-
nal. Computing this information, ignition si gnals are transmitted to the power transistor.
During the following conditions, the ignition timing is revi sed 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:0000000004537022
INPUT/OUTPUT SIGNAL CHART Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed*2
Piston position
Ignition timing
control Power 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
ABS actuator and electric unit (control unit) Vehicle speed*1
Combination meter 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
ABS actuator and electric unit (control unit) Vehicle speed*
Combination meter

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AIR CONDITIONING
CUT CONTROL
Input/Output Signal Chart INFOID:0000000004537023
*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 INFOID:0000000004537024
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 control Air conditioner relay
Accelerator pedal position sensor Accelerator pedal position
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE) Engine speed*
2
Engine coolant temperature sensor Engine coolant temperature
Battery Battery voltage*2
Refrigerant pressure sensor Refrigerant pressure
EPS control unit Power steering operation*1
ABS actuator and electric unit (control unit) Vehicle speed*1
Combination meter

ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-551
< SERVICE INFOMATION >
[MR TYPE 1] C
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• Sea level
• Flat road
• Ambient air temperature: 20 - 30 °C (68 - 86 °F)
• Diagnosis is performed as quickly as possible under normal conditions.
Under different conditions [For example: ambient air temperature other than 20 - 30 °C (68 - 86 °F)], diagno-
sis may also be performed.
Pattern 1:
• The engine is started at the engine coolant temperature of −10 to 35 °C (14 to 95 °F)
(where the voltage between the ECM terminal 38 and ground is 3.0 - 4.3V).
• The engine must be operated at idle speed until the engine coolant temperature is greater than 70 °C
(158 °F) (where the voltage between the ECM te rminal 38 and ground is lower than 1.4V).
• The engine is started at the fuel tank temperature of warmer than 0 °C (32 °F) (where the voltage
between the ECM terminal 43 and ground is less than 4.1V).
Pattern 2:
• When steady-state driving is performed again even afte r it is interrupted, each diagnosis can be conducted.
In this case, the time required for diagnosis may be extended.
Pattern 3:
• Operate vehicle following the driving pattern shown in the figure.
• Release the accelerator pedal during decelerating vehicle speed
from 90 km/h (56 MPH) to 0 km/h (0 MPH).
Pattern 4:
• The accelerator pedal must be held very steady during steady-
state driving.
• If the accelerator pedal is moved, the test must be conducted all over again.
*1: Depress the accelerator pedal until vehicle speed is 90 km/h (56
MPH), then release the accelerator pedal and keep it released for
more than 10 seconds. Depress the accelerator pedal until vehicle
speed is 90 km/h (56 MPH) again.
*2: Checking the vehicle speed with GST is advised.
Suggested Transmission Gear Po sition for A/T and CVT Models
Set the selector lever in the D position (CVT), D position with the overdrive switch turned ON (A/T).
Suggested upshift speeds for M/T models
Shown below are suggested vehicle speeds for shifting into a higher gear. These suggestions relate to fuel
economy and vehicle performance. Actual upshift speeds will vary according to road conditions, the weather
and individual driving habits.
Suggested Maximum Speed in Each Gear
Downshift to a lower gear if the engine is not running smoothly, or if you need to accelerate.
Do not exceed the maximum suggested speed (shown below) in any gear. For level road driving, use the high-
est gear suggested for that speed. Always observe post ed speed limits and drive according to the road condi-
tions to ensure safe operation. Do not over-rev t he engine when shifting to a lower gear as it may cause
engine damage or loss of vehicle control. PBIB2244E
For normal accelera
tion in low alti-
tude areas
[less than 1,219 m (4,000 ft)]: For quick acceleration in low alti-
tude areas For high attitude areas
[over 1,219m (4,000 ft)]:
Gear change ACCEL shift point km/h (MPH) km/h (MPH) km/h (MPH)
1st to 2nd 13 (8) 24 (15) 24 (15)
2nd to 3rd 27 (17) 40 (25) 40 (25)
3rd to 4th 40 (25) 53 (33) 65 (40)
4th to 5th 58 (36) 71 (44) 73 (45)
5th to 6th 82 (51) 82 (51) 82 (51)

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All components and systems should be monitored at least once by the OBD system.
• The B counter will be cleared when the malfunction is detected once regardless of the driving pattern.
• The B counter will be counted up when driving pattern B is satisfied without any malfunction.
• The MIL will go off when the B counter reaches 3. (*2 in “OBD SYSTEM OPERATION CHART”)
Driving pattern C means the vehicle operation as follows:
The following conditions should be satisfied at the same time:
Engine speed: (Engine speed in the freeze frame data) ±375 rpm
Calculated load value: (Calculated load value in the freeze frame data) x (1 ±0.1) [%]
Engine coolant temperature (T) condition:
• When the freeze frame data shows lower than 70 °C (158 °F), “T” should be lower than 70 °C (158 °F).
• When the freeze frame data shows higher than or equal to 70 °C (158 °F), “T” should be higher than or equal
to 70 °C (158 °F).
Example:
If the stored freeze frame data is as follows:
Engine speed: 850 rpm, Calculated load val ue: 30%, Engine coolant temperature: 80°C (176 °F)
To be satisfied with driving pattern C, the v ehicle should run under the following conditions:
Engine speed: 475 - 1,225 rpm, Calculated load value: 27 - 33%, Engine coolant temperature: more than 70°C
(158 °F)
• The C counter will be cleared when the malfunction is detected regardless of vehicle conditions above.
• The C counter will be counted up when vehicle conditions above is satisfied without the same malfunction.
• The DTC will not be displayed after C counter reaches 80.
• The 1st trip DTC will be cleared when C counter is counted once without the same malfunction after DTC is
stored in ECM.
RELATIONSHIP BETWEEN MIL, DTC, 1ST TRIP DTC AND DRIVING PATTERNS EXCEPT FOR
“MISFIRE ”, “FUEL INJECTION SYSTEM”

EC-566< SERVICE INFOMATION >
[MR TYPE 1]
BASIC SERVICE PROCEDURE
BASIC SERVICE PROCEDURE
Basic Inspection INFOID:00000000045370431.
INSPECTION START
1. Check service records for any recent repairs that ma y indicate a related malfunction, or a current need for
scheduled maintenance.
2. Open engine hood and check the following:
- Harness connectors for improper connections
- Wiring harness for improper connections, pinches and cut
- Vacuum hoses for splits, kinks and improper connections
- Hoses and ducts for leaks
- Air cleaner clogging
- Gasket
3. Confirm that electrical or mechanical loads are not applied.
- Headlamp switch is OFF.
- Air conditioner switch is OFF.
- Rear window defogger switch is OFF.
- Steering wheel is in the straight-ahead position, etc.
4. Start engine and warm it up until engine coolant temperature indicator points the middle of gauge.
Ensure engine stays below 1,000 rpm.
5. Run engine at about 2,000 rpm for about 2 minutes under no load.
6. Make sure that no DTC is displayed with CONSULT-III or GST.
OK or NG OK >> GO TO 3.
NG >> GO TO 2. 2.
REPAIR OR REPLACE
Repair or replace components as necessary according to corresponding Diagnostic Procedure.
>> GO TO 3. 3.
CHECK TARGET IDLE SPEED
With CONSULT-III
1. Run engine at about 2,000 rpm for about 2 minutes under no load. SEF983U
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