NISSAN TIIDA 2008 Service Repair Manual

PRECAUTIONS
EC-17
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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

EC-18
< SERVICE INFORMATION >
PRECAUTIONS
•Before replacing ECM, perform “ECM Terminals and Refer-
ence Value” inspection and make sure ECM functions prop-
erly. Refer to EC-102, "
ECM Terminal and Reference Value".
•Handle mass air flow sensor carefully to avoid damage.
•Do not disassemble mass air flow sensor.
•Do not clean mass air flow sensor with any type of detergent.
•Do not disassemble electric throttle control actuator.
•Even a slight leak in the air intake system can cause serious
incidents.
•Do not shock or jar the camshaft position sensor (PHASE),
crankshaft position sensor (POS).
•After performing each TROUBLE DIAGNOSIS, perform DTC
Confirmation Procedure or Overall Function Check.
The DTC should not be displayed in the DTC Confirmation
Procedure if the repair is completed. The Overall Function
Check should be a good result if the repair is completed.
•When measuring ECM signals with a circuit tester, never allow
the two tester probes to contact.
Accidental contact of probes will cause a short circuit and
damage the ECM power transistor.
•Do not use ECM ground terminals when measuring input/out-
put voltage. Doing so may result in damage to the ECM's tran-
sistor. Use a ground other than ECM terminals, such as the
ground.
•Do not operate fuel pump when there is no fuel in lines.
•Tighten fuel hose clamps to the specified torque.
-Fuel level sensor unit and fuel pump (1)
-Fuel pressure regulator (2)
-Fuel level sensor (3)
-Fuel tank temperature sensor (4)
MEF040D
SEF217U
SEF348N
BBIA0704E

PRECAUTIONS
EC-19
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•Do not depress accelerator pedal when starting.
•Immediately after starting, do not rev up engine unnecessar-
ily.
•Do not rev up engine just prior to shutdown.
•When installing C.B. ham radio or a mobile phone, be sure to
observe the following as it may adversely affect electronic
control systems depending on installation location.
-Keep the antenna as far as possible from the electronic con-
trol units.
-Keep the antenna feeder line more than 20 cm (8 in) away
from the harness of electronic controls.
Do not let them run parallel for a long distance.
-Adjust the antenna and feeder line so that the standing-wave
radio can be kept smaller.
-Be sure to ground the radio to vehicle body.
SEF709Y
SEF708Y

EC-20
< SERVICE INFORMATION >
PREPARATION
PREPARATION
Special Service ToolINFOID:0000000001702552
The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Tool number
(Kent-Moore No.)
Tool nameDescription
KV10117100
(J-36471-A)
Heated oxygen sensor
wrenchLoosening or tightening heated oxygen sensor
with 22 mm (0.87 in) hexagon nut
KV10114400
(J-38365)
Heated oxygen sensor
wrenchLoosening or tightening heated oxygen sensor
a: 22 mm (0.87 in)
(J-44321)
Fuel pressure gauge
KitChecking fuel pressure
(J-44321-6)
Fuel pressure adapterConnecting fuel pressure gauge to quick connec-
tor type fuel lines.
KV10118400
Fuel tube adapterMeasuring fuel pressure
S-NT379
S-NT636
LEC642
LBIA0376E
PBIB3043E

PREPARATION
EC-21
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Commercial Service ToolINFOID:0000000001702553
Tool number
(Kent-Moore No.)
Tool nameDescription
Leak detector
i.e.: (J-41416)Locating the EVAP leak
EVAP service port
adapter
i.e.: (J-41413-OBD)Applying positive pressure through EVAP service
port
Fuel filler cap adapter
i.e.: (MLR-8382)Checking fuel tank vacuum relief valve opening
pressure
Socket wrench Removing and installing engine coolant tempera-
ture sensor
Oxygen sensor thread
cleaner
i.e.: (J-43897-18)
(J-43897-12)Reconditioning 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)Lubricating oxygen sensor thread cleaning tool
when reconditioning exhaust system threads.
S-NT703
S-NT704
S-NT815
S-NT705
AEM488
S-NT779

EC-22
< SERVICE INFORMATION >
ENGINE CONTROL SYSTEM
ENGINE CONTROL SYSTEM
SchematicINFOID:0000000001702554
Multiport Fuel Injection (MFI) SystemINFOID:0000000001702555
INPUT/OUTPUT SIGNAL CHART
PBIB3331E

ENGINE CONTROL SYSTEM
EC-23
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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

EC-24
< SERVICE INFORMATION >
ENGINE CONTROL SYSTEM
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 the sensor voltage signal. For more information about air
fuel ratio (A/F) sensor 1, refer to EC-213
. 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 (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 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 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 mixture 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 basic 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 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 air fuel ratio (A/F) sensor 1 indicates whether the mixture ratio is RICH or LEAN com-
pared to the theoretical 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.
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 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.
This system is used when the engine is being started and/or if the fail-safe system (CPU) is operating.
SEF337W

ENGINE CONTROL SYSTEM
EC-25
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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*

EC-26
< SERVICE INFORMATION >
ENGINE CONTROL SYSTEM
If the engine speed is above 2,000 rpm under no load [for example, the shift lever position is P or N (A/T,
CVT), Neutral (M/T) and engine speed is over 2,000 rpm] fuel will be cut off after some time. The exact time
when the fuel is cut off varies based on engine speed.
Fuel cut will be operated until the engine speed reaches 1,500 rpm, then fuel cut will be cancelled.
NOTE:
This function is different from deceleration control listed under EC-22, "
Multiport Fuel Injection (MFI) System".