fuel NISSAN TEANA 2014 Repair Manual

SYSTEMEC-47
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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
• High-load, high-speed operation

• During deceleration
• During high engine speed operation
MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)
The mixture ratio feedback system prov ides 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 A/F
sensor 1 in the exhaust manifold to monitor whether t he engine operation is rich or lean. The ECM adjusts the
injection pulse width according to the sensor voltage si gnal. For more information about A/F sensor 1, refer to
EC-32, "Air Fuel Ratio (A/F) Sensor 1"
. This maintains the mixture rati o 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 A/F sensor 1 shift, the air-fuel rati o 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 A/F sensor 1 or its circuit
- Insufficient activation of A/F sensor 1 at low engine coolant temperature
- High engine coolant temperature
- During warm-up
- After shifting from N to D
- When starting the engine
MIXTURE RATIO SELF-LEARNING CONTROL
The mixture ratio feedback control system monitors the mixture ratio signal transmitted from A/F sensor 1.
This feedback signal is then sent to the ECM. The ECM cont rols the basic mixture ratio as close to the theoret-
ical mixture ratio as possible. However, the basic mi xture ratio is not necessarily controlled as originally
designed. Both manufacturing differences (i.e., mass air flow sensor hot wire) and characteristic changes dur-
ing 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.
PBIB2793E
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EC-48
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SYSTEM
“Short term fuel trim” is the short-term fuel compensati
on used to maintain the mixture ratio at its theoretical
value. The signal from A/F sensor 1 indicates whether the mixture ratio is RICH or LEAN compared to the the-
oretical 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 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 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 cylinder s twice each engine cycle. In other words, pulse signals
of the same width are simultaneously transmitted from the ECM.
The four 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.
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.
ELECTRIC IGNITION SYSTEM
ELECTRIC IGNITION SYSTEM : System DescriptionINFOID:0000000009462095
SYSTEM DIAGRAM
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.
SEF337W
JPBIA3193GB
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SYSTEMEC-49
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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.
INTAKE VALVE TIMING CONTROL
INTAKE VALVE TIMING CONTROL : System DescriptionINFOID:0000000009462096
INTAKE VALVE TIMING CONTROL
System Diagram
Input/Output Signal Chart
*: This signal is sent to the ECM through CAN communication line
JPBIA4760GB
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed and piston position
Intake valve
timing control Intake valve timing control
solenoid valve
Camshaft position sensor (PHASE)
Engine oil temperature sensor Engine oil temperature
Engine coolant temperature sensor Engine coolant temperature
Combination meter Vehicle speed*
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SYSTEMEC-53
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SYSTEM DESCRIPTION
This mechanism hydraulically controls cam phases c
ontinuously with the fixed operating angle of the exhaust
valve.
The ECM receives signals such as crankshaft position, camshaft position, engine speed, and engine oil tem-
perature. Then, the ECM sends ON/OFF pulse duty signal s to the exhaust valve timing (EVT) control solenoid
valve depending on driving status. This makes it possible to control the shut/open timing of the exhaust valve
to increase engine torque and output in a range of high engine speed.
INTAKE MANIFOLD RUNNER CONTROL
INTAKE MANIFOLD RUNNER CONTROL : System DescriptionINFOID:0000000009462098
SYSTEM DIAGRAM
SYSTEM DESCRIPTION
Intake manifold runner control valve has a valve portion in the intake passage of each cylinder.
While idling and during low engine coolant temperature, t he intake manifold runner control valve closes. Thus
the velocity of the air in the intake passage increases , promoting the vaporization of the fuel and producing a
intake manifold runner in the combustion chamber.
Because of this operation, this system tends to in crease the burning speed of the gas mixture, improve
exhaust emission, and increase the stability in running conditions.
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SYSTEMEC-55
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Intake Manifold Tuning Valve Operating Condition
ECM opens the intake manifold tuning valve when all of the following conditions are satisfied.
• Engine speed: 5,000 rpm or more
• Engine coolant temperature: -30 °C (-22 °F) or more
• Battery voltage: 16 V or less
ENGINE PROTECTION CONTROL AT LOW ENGINE OIL PRESSURE
ENGINE PROTECTION CONTROL AT LOW ENGINE OIL PRESSURE : System De-
scription
INFOID:0000000009462100
SYSTEM DIAGRAM
INPUT/OUTPUT SIGNAL CHART
SYSTEM DESCRIPTION
• The engine protection control at low engine oil pressure warns the driver of a decrease in engine oil pres-
sure by the oil pressure warning lamp a before the engine becomes damaged.
• When detecting a decrease in engine oil pressure at an engine speed less than 1,000 rpm, ECM transmits an oil pressure warning lamp signal to the combination meter.The combination meter turns ON the oil pres-
sure warning lamp, according to the signal.
*: When detecting a normal engine oil pressure, ECM turns OFF the oil pressure warning lamp.
FUEL FILLER CAP WARNING SYSTEM
JPBIA4922GB
Sensor Input signal to ECM ECM function Actuator
Engine oil pressure sensor Engine pressure Engine protection control
• Oil pressure warning lamp
signal
•FUel cut control Combination meter
• Oil pressure warning lamp
Crankshaft position sensor
(POS) Engine speed
Engine oil temperature sensor Engine oil temperature
Decrease in engine oil pressure Engine speed Combination meter
Fuel cut
Oil pressure warning lamp
Detection Less than 1,000 rpm ON* NO
1,000 rpm or more ON YES
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EC-56
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SYSTEM
FUEL FILLER CAP WARNING SYS TEM : System Description
INFOID:0000000009462101
SYSTEM DIAGRAM
SYSTEM DESCRIPTION
The fuel filler cap warning system alerts the driver to the prevention of the fuel filler being left uncapped and
malfunction occurrences after refueling, by turning ON the fuel filler cap warning display on the combination
meter.
ECM judges a refueled state, based on a fuel level signal transmitted from the combination meter.
When a very small leak is detected through the EVAP leak diagnosis performed after judging the refueled
state, ECM transmits a fuel filler cap warning display signal (request for display ON) to the combination meter
via CAN communication.
When receiving the signal, the combination meter turns ON the fuel filler cap warning display.
CAUTION:
Check fuel filler cap installation condition when the fuel filler cap warning display turns ON.
Reset Operation
The fuel filler cap warning lamp tunes OFF, according to any condition listed below:
• Reset operation is performed by operating the meter control switch on the combination meter. Refer to MWI-
18, "Description".
- When the reset operation is performed, the combination meter transmits a fuel filler cap warning reset signal
to ECM via CAN communication. ECM transmits a fuel filler cap warning display signal (request for display
OFF) to the combination meter via CAN communicati on. When receiving the signal, the combination meter
turns OFF the fuel filler cap warning display.
• EVAP leak diagnosis result is normal.
• Fuel refilled.
• DTC erased by using CONSULT.
NOTE:
MIL turns ON if a malfunction is detected in leak diagnosis results again at the trip after the fuel filler cap warn-
ing display turns ON/OFF.
AIR CONDITIONING CUT CONTROL
AIR CONDITIONING CUT CONTROL : System Description (with automatic air condi-
JSBIA0797GB
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EC-62
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SYSTEM
EVAPORATIVE EMISSION SYSTEM : System Description
INFOID:0000000009462106
SYSTEM DIAGRAM
INPUT/OUTPUT SIGNAL CHART
*1: ECM determines the start signal status by the signals of engine speed and battery voltage.
*2: This signal is sent to the ECM through CAN communication line.
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Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE) Engine speed*
1
EVAP canister
purge flow control EVAP canister purge vol-
ume control solenoid valve
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Battery Battery voltage*
1
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
(Mixture ratio fe edback signal)
Fuel tank temperature sensor Fuel temperature in fuel tank
EVAP control system pressure sensor Pressure in purge line
Combination meter Vehicle speed*
2
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SYSTEMEC-63
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SYSTEM DESCRIPTION
The evaporative emission system is used to reduce hydr
ocarbons emitted into the atmosphere from the fuel
system. This reduction of hydrocarbons is accompli shed by activated charcoals in the EVAP canister.
The fuel vapor in the sealed fuel tank is led into t he EVAP canister which contains activated carbon and the
vapor is stored there when the engine is not oper ating or when refueling to the fuel tank.
The vapor in the EVAP canister is purged by the air through the purge line to the intake manifold when the
engine is operating. EVAP canister purge volume control solenoid valve is controlled by ECM. When the
engine operates, the flow rate of vapor controlled by EVAP canister purge volume control solenoid valve is
proportionally regulated as the air flow increases.
EVAP canister purge volume control solenoid valve al so shuts off the vapor purge line during decelerating.
AUTOMATIC SPEED CONTROL DEVICE (ASCD)
AUTOMATIC SPEED CONTROL DEVICE (ASCD) : System DescriptionINFOID:0000000009462107
SYSTEM DIAGRAM
BASIC ASCD SYSTEM
Refer to Owner's Manual for ASCD operating instructions.
Automatic Speed Control Device (ASCD) allows a driver to keep vehicle at predetermined constant speed
without depressing accelerator pedal. Driver can set vehicle speed in advance between approximately 40 km/
h (25 MPH) and 144 km/h (89 MPH).
ECM controls throttle angle of electric thro ttle control actuator to regulate engine speed.
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DIAGNOSIS SYSTEM (ECM)EC-67
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DIAGNOSIS SYSTEM (ECM)
DIAGNOSIS DESCRIPTION
DIAGNOSIS DESCRIPTION : 1s
t Trip Detection Logic and Two Trip Detection Logic
INFOID:0000000009462112
When a malfunction is detected for the first time, 1st tr ip DTC and 1st trip Freeze Frame data are stored in the
ECM memory. The MIL will not illuminate at this stage. <1st trip>
If the same malfunction is detected again during the next drive, the DTC and Freeze Frame data are stored in
the ECM memory, and the MIL illuminates. The MIL illu minates at the same time when the DTC is stored.
<2nd trip> The “trip” in the “Two Trip Detection Logic” means a driving mode in which self-diagnosis is per-
formed during vehicle operation. Specific on board diagnosti c items will cause the ECM to illuminate or blink
the MIL, and store DTC and Freeze Frame data, even in the 1st trip, as shown below.
×: Applicable —: Not applicable
DIAGNOSIS DESCRIPTION : DTC and Freeze Frame DataINFOID:0000000009462113
DTC AND 1ST TRIP DTC
The 1st trip DTC (whose number is the same as the DT C number) is displayed for the latest self-diagnostic
result obtained. If the ECM memory was cleared previously , and the 1st trip DTC did not recur, the 1st trip DTC
will not be displayed.
If a malfunction is detected during the 1st trip, the 1st trip DTC is saved in the ECM memory. The MIL will not
light up (two trip detection logic). If the same malfunc tion is not detected in the 2nd trip (meeting the required
driving pattern), the 1st trip DTC is cleared from the ECM memory. If the same malfunction is detected in the
2nd trip, both the 1st trip DTC and DTC are saved in t he ECM memory and the MIL lights up. In other words,
the DTC is stored in the ECM memory and the MIL light s up when the same malfunction occurs in two consec-
utive trips. If a 1st trip DTC is stored and a non-diagnostic operation is performed between the 1st and 2nd
trips, only the 1st trip DTC will continue to be stored. Fo r malfunctions that blink or light up the MIL during the
1st trip, the DTC and 1st trip DTC are stored in the ECM memory.
For malfunctions in which 1st trip DTCs are displayed, refer to EC-105, "DTC Index"
. These items are
required by legal regulations to c ontinuously monitor the system/component . In addition, the items monitored
non-continuously are also displayed on CONSULT.
1st trip DTC is specified in Service $07 of SAE J1979/ ISO 15031-5. 1st trip DTC detection occurs without illu-
minating the MIL and therefore does not warn the driver of a malfunction.
When a 1st trip DTC is detected, check, print out or write down and erase (1st trip) DTC and Freeze Frame
data as specified in Work Flow procedure Step 2, refer to EC-165, "Work Flow"
. Then perform DTC Confirma-
tion Procedure or Component Function Check to try to duplicate the malfunction. If the malfunction is dupli-
cated, the item requires repair.
FREEZE FRAME DATA AND 1ST TRIP FREEZE FRAME DATA
The ECM records the driving conditions such as fuel system status, calculated load value, engine coolant tem-
perature, short term fuel trim, long term fuel trim, engi ne speed, vehicle speed, absolute throttle position, base
fuel schedule and intake air temperature at the moment a malfunction is detected.
Data which are stored in the ECM memory, along with the 1st trip DTC, are called 1st trip freeze frame data.
The data, stored together with the DTC data, are called freeze frame data and displayed on CONSULT or
GST. The 1st trip freeze frame data c an only be displayed on the CONSULT screen.
Items MIL DTC 1st trip DTC
1st trip 2nd trip 1st trip
displaying 2nd trip
displaying 1st trip
displaying 2nd trip
display- ing
Blinking Illuminat-
ed Blinking Illuminat-
ed
Misfire (Possible three way catalyst
damage) — DTC: P0300 – P0304
is being detected ×
———— — ×—
Misfire (Possible three way catalyst
damage) — DTC: P0300 – P0304
is being detected ——
×—— ×——
One trip detection diagnoses (Re-
fer to EC-105, "DTC Index"
.) —
×—— ×———
Except above — — — ×— ×× —
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EC-68
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DIAGNOSIS SYSTEM (ECM)
Only one set of freeze frame data (either 1st trip freez
e frame data or freeze frame data) can be stored in the
ECM. 1st trip freeze frame data is stored in the ECM me mory along with the 1st trip DTC. There is no priority
for 1st trip freeze frame data and it is updated each time a different 1st trip DTC is detected. However, once
freeze frame data (2nd trip detection/MIL on) is stored in the ECM memory, 1st trip freeze frame data is no
longer stored. Remember, only one set of freeze frame data can be stored in the ECM. The ECM has the fol-
lowing priorities to update the data.
For example, the EGR malfunction (Priority: 2) was detected and the freeze frame data was saved in the 2nd
trip. After that when the misfire (Priority: 1) is detected in another trip, the freeze frame data will be updated
from the EGR malfunction to the misfire. The 1st trip freeze frame data is updated each time a different mal-
function is detected. There is no priority for 1st trip freeze frame data. However, once freeze frame data is
stored in the ECM memory, 1st trip freeze data is no longer stored (because only one freeze frame data or 1st
trip freeze frame data can be stored in the ECM). If fr eeze frame data is stored in the ECM memory and freeze
frame data with the same priority occurs later, t he first (original) freeze frame data remains unchanged in the
ECM memory.
Both 1st trip freeze frame data and freeze frame dat a (along with the DTCs) are cleared when the ECM mem-
ory is erased.
DIAGNOSIS DESCRIPTION : Counter SystemINFOID:0000000009462114
RELATIONSHIP BETWEEN MIL, 1ST TRIP DTC, DTC, AND DETECTABLE ITEMS
• When a malfunction is detected for the first time, the 1st trip DTC and the 1st trip freeze frame data are
stored in the ECM memory.
• When the same malfunction is detected in two consec utive trips, the DTC and the freeze frame data are
stored in the ECM memory, and the MIL will come on.
• The MIL will turn OFF after the vehicle is driven 3 time s (driving pattern B) with no malfunction. The drive is
counted only when the recorded driving pattern is met (as stored in the ECM). If another malfunction occurs
while counting, the counter will reset.
• The DTC and the freeze frame data will be stored until the vehicle is driven 40 times (driving pattern A) with-
out the same malfunction recurring (except for Misfire and Fuel Injection System). For Misfire and Fuel Injec-
tion System, the DTC and freez e frame data will be stored until the vehicle is driven 80 times (driving pattern
C) without the same malfunction recurring. The “TIM E” in “SELF-DIAGNOSTIC RESULTS” mode of CON-
SULT will count the number of times the vehicle is driven.
• The 1st trip DTC is not displayed when the self-diagnosis results in OK for the 2nd trip.
COUNTER SYSTEM CHART
For details about patterns B and C under “Fuel Inject ion System” and “Misfire”, see “EXPLANATION FOR
DRIVING PATTERNS FOR “MISFIRE ”, “FUEL INJECTION SYS-
TEM”.
For details about patterns A and B under Other, s ee “EXPLANATION FOR DRIVING PATTERNS FOR “MIS-
FIRE ”, “FUEL INJECTION SYSTEM”.
• *1: Clear timing is at the moment OK is detected.
• *2: Clear timing is when the same ma lfunction is detected in the 2nd trip.
Relationship Between MIL, DTC, 1st Trip DTC and Driving Patterns for “Misfire terioration>”, “Fuel Injection System”
Priority Items
1 Freeze frame data Misfire — DTC: P0300 – P0304
Fuel Injection System Function — DTC: P0171, P0172
2 Except the above items
3 1st trip freeze frame data
Items Fuel Injection System Misfire Other
MIL (turns OFF) 3 (pattern B) 3 (pattern B) 3 (pattern B)
DTC, Freeze Frame Data (no display) 80 (p attern C) 80 (pattern C) 40 (pattern A)
1st Trip DTC (clear) 1 (pattern C), *1 1 (pattern C), *1 1 (pattern B)
1st Trip Freeze Frame Data (clear) *1, *2 *1, *2 1 (pattern B)
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