engine coolant NISSAN TEANA 2014 Repair Manual

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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EC-54
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SYSTEM
Also, except when idling and during low engine coolant te
mperature, this system opens the intake manifold
runner control valve.
In this condition, this system tends to increase power by improving intake efficiency via reduction of intake flow
resistance.
The intake manifold runner control valve is operated by the ECM.
INTAKE MANIFOLD TUNING SYSTEM
INTAKE MANIFOLD TUNING SYSTEM : System DescriptionINFOID:0000000009462099
SYSTEM DIAGRAM
SYSTEM DESCRIPTION
This system switches the length of intake air path according to the low-to-medium speed range or high speed
range. Torque is increased in the low-to-medium sp eed range and the engine output is improved in the high
speed range.
Engine speed: Low and medium speed range
Since the intake manifold tuning (IMT) valve is closed when the engine speed is less than 5,000 rpm, the
length of the effective intake air path is from the mouth of intake manifold collector to the intake valve. This
long path brings the inertia effect of intake air, cont ributing to the improvement in intake air efficiency and the
generation of high torque.
Engine speed: High speed range
When engine speed is 5,000 rpm or more, ECM turns ON the intake manifold tuning valve motor to open the
intake manifold tuning valve. The length of the effective in take air path at this time is from the intake manifold
tuning valve to the intake valve. This short path brings the inertia effect of intake air in the high speed range,
contributing to the torque improvement while the engine is running at high speeds. (The highest engine output
is improved.)
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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
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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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SYSTEMEC-57
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tioner)INFOID:0000000009462102
SYSTEM DIAGRAM
SYSTEM DESCRIPTION
This system improves engine operation when the air conditioner is used.
Under the following conditions, the air conditioner is turned off.
• 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.
AIR CONDITIONING CUT CONTROL : System Description (with manual air condition-
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EC-58
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SYSTEM
er)
INFOID:0000000009462103
SYSTEM DIAGRAM
SYSTEM DESCRIPTION
This system improves engine operati on when the air conditioner is used.
Under the following conditions, the air conditioner is turned off.
• When cranking the engine.
• At high engine speeds.
• When the engine coolant temperat ure 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.
COOLING FAN CONTROL
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SYSTEMEC-59
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COOLING FAN CONTROL : System Descripti
on (with automatic air conditioner)
INFOID:0000000009462104
SYSTEM DIAGRAM
SYSTEM DESCRIPTION
ECM controls cooling fan speed corresponding to vehicle speed, engine coolant temperature, refrigerant pres-
sure, air conditioner ON signal. Then control syst em has 4-step control [HIGH/MIDDLE/LOW/OFF].
Cooling Fan Operation
Cooling Fan Relay Operation
The ECM controls cooling fan relays through CAN communication line.
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EC-60
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SYSTEM
COOLING FAN CONTROL : S ystem Description (with manual air conditioner)
INFOID:0000000009462105
SYSTEM DIAGRAM
SYSTEM DESCRIPTION
ECM controls cooling fan speed corresponding to vehicle speed, engine coolant temperature, refrigerant pres-
sure, air conditioner ON signal. Then control syst em has 4-step control [HIGH/MIDDLE/LOW/OFF].
Cooling fan speed Cooling fan relay
123
Stop (OFF) OFF OFF OFF
Low (LOW) ON OFF OFF
Middle (MID) OFF ON OFF
High (HI) OFF ON ON
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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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EC-64
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SYSTEM
The ASCD operation status is indicated by two indica
tors (CRUISE and SET on the information display) on the
combination meter. If any malfunction occurs in AS CD system, SET indicator blinks and ASCD control is deac-
tivated.
NOTE:
Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws.
SET OPERATION
Press MAIN switch. (CRUISE is indicated on the information display.)
When vehicle speed reaches a desired speed between approximately 40 km/h (25 MPH) and 144 km/h (89
MPH), press SET/COAST switch. (Then SET is indicated on the information display.)
ACCELERATE OPERATION
If the RESUME/ACCELERATE switch is pressed during cruise control driving, increase the vehicle speed until
the switch is released or vehicle speed r eaches maximum speed controlled by the system.
And then ASCD will keep the new set speed.
CANCEL OPERATION
When any of following conditions exist, cruise operation will be canceled.
• CANCEL switch is pressed
• More than 2 switches at ASCD steering switch are pressed at the same time (Set speed will be cleared)
• Brake pedal is depressed
• Selector lever is changed to N, P, R position
• Vehicle speed decreased to 13 km/h (8 MPH) lower than the set speed
• TCS system is operated
When the ECM detects any of the following conditions , the ECM will cancel the cruise operation and inform
the driver by blinking indicators.
• Engine coolant temperature is slightly higher than t he normal operating temperature, CRUISE indicator may
blink slowly.
When the engine coolant temperature decreases to the normal operating temperature, CRUISE indicator will
stop blinking and the cruise operation will be able to wo rk by pressing SET/COAST switch or RESUME/
ACCELERATE switch.
• Malfunction for some self-diagnoses regarding AS CD control: SET indicator will blink quickly.
If MAIN switch is turned to OFF during ASCD is acti vated, all of ASCD operations will be canceled and vehicle
speed memory will be erased.
COAST OPERATION
When the SET/COAST switch is press ed during cruise control driving, decrease vehicle set speed until the
switch is released. And then ASCD will keep the new set speed.
RESUME OPERATION
When the RESUME/ACCELERATE switch is pressed after cancel operation other than pressing MAIN switch
is performed, vehicle speed will return to last set s peed. To resume vehicle set speed, vehicle condition must
meet following conditions.
• Brake pedal is released
• Selector lever is in other than P and N positions
• Vehicle speed is greater than 40 km/h (25 MPH) and less than 144 km/h (89 MPH)
CAN COMMUNICATION
CAN COMMUNICATION : System DescriptionINFOID:0000000009462108
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication s peed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CA N communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.
Refer to LAN-32, "CAN COMMUNICA TION SYSTEM : CAN Communication Signal Chart"
, about CAN com-
munication for detail.
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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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