STRUCTURE AND OPERATIONEC-563
< SYSTEM DESCRIPTION > [VQ35DE]
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STRUCTURE AND OPERATION
Positive Crankcase Ventilation (PCV)INFOID:0000000009462511
This system returns blow-by gas to the intake manifold.
The positive crankcase ventilation (PCV) valve is prov ided to conduct crankcase blow-by gas to the intake
manifold.
During partial throttle operation of the engine, the in take manifold sucks the blow-by gas through the PCV
valve.
Normally, the capacity of the valve is sufficient to handle any blow-by and a small amount of ventilating air.
The ventilating air is drawn from the air inlet tubes in to the crankcase. In this process the air passes through
the hose connecting air inlet tubes to rocker cover.
Under full-throttle condition, the manifold vacuum is in sufficient to draw the blow-by flow through the valve.
The flow goes through the hose connection in the reverse direction.
On vehicles with an excessively high blow-by, the valve does not
meet the requirement. This is because some of the flow will go
through the hose connection to the air inlet tubes under all condi-
tions.
SEC921C
PBIB1588E
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EC-564
< SYSTEM DESCRIPTION >[VQ35DE]
STRUCTURE AND OPERATION
On Board Refueling V apor Recovery (ORVR)
INFOID:0000000009462512
From the beginning of refueling, the air and vapor insi de the fuel tank go through refueling EVAP vapor cut
valve and EVAP/ORVR line to the EVAP canister. The vapor is absorbed by the EVAP canister and the air is
released to the atmosphere.
When the refueling has reached the full level of the fuel tank, the refueling EVAP vapor cut valve is closed and
refueling is stopped because of auto shut-off. The vapor which was absorbed by the EVAP canister is purged
during driving.
WARNING:
When conducting inspections below, be sure to observe the following:
• Put a “CAUTION: FLAMMABLE” sign in workshop.
• Never smoke while servicing fuel system. Keep open flames and sparks away from work area.
• Always to furnish the workshop with a CO
2 fire extinguisher.
CAUTION:
• Before removing fuel line parts, carry out the following procedures:
- Put drained fuel in an explosion-pr oof container and put lid on securely.
- Release fuel pressure from fuel line. Refer to EC-687, "Work Procedure"
.
- Disconnect battery ground cable.
• Always replace O-ring when the fu el gauge retainer is removed.
• Never kink or twist hose and tube when they are installed.
• Never tighten hose and clamps excessively to avoid damaging hoses.
• After installation, run engine and check for fuel leakage at connections.
• Never attempt to top off the fuel tank after the fuel pump nozzle shuts off automatically.
Continued refueling may cause fuel overflow, r esulting in fuel spray and possibly a fire.
PBIB1068E
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EC-582
< SYSTEM DESCRIPTION >[VQ35DE]
SYSTEM
Manual Air Conditioning System
INPUT/OUTPUT SIGNAL CHART
*1: ECM determines the start signal status
by the signals of engine speed and battery voltage.
*2: Automatic air conditioning system
*3: Manual air conditioning system
SYSTEM DESCRIPTION
ECM calculates the value of signal transmitted from t he accelerator pedal and activates the throttle valve by
transmitting a control signal to the electric throttle c ontrol actuator. This allows the optimum throttle angle and
improves drivability and fuel consumption. In addition, ECM learns the fully closed position every time when
the ignition switch is turned OFF to improv e the accuracy in throttle valve position.
When a malfunction occurs in the throttle control system , the throttle valve is closed by the return spring and
maintains the minimum engine speed by holding a slightly opened condition which is close to the fully opened
condition. This allows the securing of brake syste m, power steering system, and electric system and the
ensuring of the safety.
INTAKE VALVE TIMING CONTROL
JSBIA1917GB
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed
*1
Throttle controlElectric throttle control
actuator
Engine coolant temperature sensor Engine coolant temperature
Mass air flow sensor Amount of intake air
Intake air temperature sensor Intake air temperature
Accelerator pedal position sensor Accelerator pedal position
Ignition switch Start signal and ignition OFF
Combination meter CAN communi-
cation Vehicle speed signal
A/C auto amp.
*2CAN communi-
cation • A/C ON signal
• Blower fan ON signal
BCM
*3
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DIAGNOSIS SYSTEM (ECM)EC-591
< SYSTEM DESCRIPTION > [VQ35DE]
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DIAGNOSIS SYSTEM (ECM)
DIAGNOSIS DESCRIPTION
DIAGNOSIS DESCRIPTION : 1s
t Trip Detection Logic and Two Trip Detection Logic
INFOID:0000000009462533
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:0000000009462534
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-630, "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-670, "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 – P0308
is being detected ×
———— — ×—
Misfire (Possible three way catalyst
damage) — DTC: P0300 – P0308
is being detected ——
×—— ×——
One trip detection diagnoses (Re-
fer to EC-630, "DTC Index"
.) —
×—— ×———
Except above — — — ×— ×× —
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EC-592
< SYSTEM DESCRIPTION >[VQ35DE]
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:0000000009462535
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
TEM”.
For details about patterns A and B under Other, s ee “EXPLANATION FOR DRIVING PATTERNS FOR “MIS-
FIRE
• *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
Priority Items
1 Freeze frame data Misfire — DTC: P0300 – P0308
Fuel Injection System Function — DTC: P0171, P0172, P0174, P0175
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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DIAGNOSIS SYSTEM (ECM)EC-593
< SYSTEM DESCRIPTION > [VQ35DE]
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Explanation for Driving Patterns for “Misfire
Driving Pattern B
Refer to EC-595, "DIAGNOSIS DESCRIPTION : Driving Pattern".
*1: When the same malfunction is de-
tected in two consecutive trips, MIL
will light up. *2: MIL will turn OFF after vehicle is driv-
en 3 times (pattern B) without any
malfunctions. *3: When the same malfunction is de-
tected in two consecutive trips, the
DTC and the freeze frame data will be
stored in ECM.
*4: The DTC and the freeze frame data will not be displayed any longer after
vehicle is driven 80 times (pattern C)
without the same malfunction. (The
DTC and the freeze frame data still
remain in ECM.) *5: When a malfunction is detected for
the first time, the 1st trip DTC and the
1st trip freeze frame data will be
stored in ECM. *6: The 1st trip DTC and the 1st trip
freeze frame data will be cleared at
the moment OK is detected.
*7: When the same malfunction is de- tected in the 2nd trip, the 1st trip
freeze frame data will be cleared. *8: 1st trip DTC will be cleared when ve-
hicle is driven once (pattern C) with-
out the same malfunction after DTC
is stored in ECM.
JMBIA1417GB
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DIAGNOSIS SYSTEM (ECM)EC-595
< SYSTEM DESCRIPTION > [VQ35DE]
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Explanation for Driving Patterns Except for “Misfire
System”
Driving Pattern A
Refer to EC-595, "DIAGNOSIS DESCRIPTION : Driving Pattern".
Driving Pattern B
Refer to EC-595, "DIAGNOSIS DESCRIPTION : Driving Pattern".
DIAGNOSIS DESCRIPTION : Driving PatternINFOID:0000000009462536
CAUTION:
Always drive at a safe speed.
DRIVING PATTERN A
Driving pattern A means a trip satisfying the following conditions.
• Engine speed reaches 400 rpm or more.
• Engine coolant temperature rises by 20 °C (36 °F) or more after starting the engine.
• Engine coolant temperature reaches 70 °C (158 °F) or more.
• The ignition switch is turned from ON to OFF.
NOTE:
• When the same malfunction is detected regardless of driv ing conditions, reset the counter of driving pattern
A.
• When the above conditions are satisfied without detecting t he same malfunction, reset the counter of driving
pattern A.
DRIVING PATTERN B
Driving pattern B means a trip satisfying the following conditions.
• Engine speed reaches 400 rpm or more.
• Engine coolant temperature reaches 70 °C (158 °F) or more.
• Vehicle speed of 70 – 120 km/h (44 – 75 MPH) is maintained for 60 seconds or more under the control of closed loop.
• Vehicle speed of 30 – 60 km/h (19 – 37 MPH) is maintained for 10 seconds or more under the control of closed loop.
• Under the closed loop control condition, the following state reaches 12 seconds or more in total: Vehicle
speed of 4 km/h (2 MPH) or less with idling condition.
• The state of driving at 10 km/h (7 MPH) or more reaches 10 minutes or more in total.
• A lapse of 22 minutes or more after engine start.
NOTE:
• Drive the vehicle at a constant velocity.
• When the same malfunction is detected regardless of driv ing conditions, reset the counter of driving pattern
B.
• When the above conditions are satisfied without detecting t he same malfunction, reset the counter of driving
pattern B.
DRIVING PATTERN C
Driving pattern C means operating vehicle as per the following:
The following conditions should be satisfied at the same time:
Engine speed: (Engine speed in the freeze frame data) ±375 rpm
*1: When the same malfunction is de-
tected in two consecutive trips, MIL
will light up. *2: MIL will turn OFF after vehicle is driv-
en 3 times (pattern B) without any
malfunctions. *3: When the same malfunction is de-
tected in two consecutive trips, the
DTC and the freeze frame data will be
stored in ECM.
*4: The DTC and the freeze frame data will not be displayed any longer after
vehicle is driven 40 times (pattern A)
without the same malfunction.
(The DTC and the freeze frame data
still remain in ECM.) *5: When a malfunction is detected for
the first time, the 1st trip DTC and the
1st trip freeze frame data will be
stored in ECM. *6: 1st trip DTC will be cleared after vehi-
cle is driven once (pattern B) without
the same malfunction.
*7: When the same malfunction is de- tected in the 2nd trip, the 1st trip
freeze frame data will be cleared.
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EC-596
< SYSTEM DESCRIPTION >[VQ35DE]
DIAGNOSIS SYSTEM (ECM)
Calculated load value: (Calculated load value in the freeze frame data) x (1
±0.1) [%]
Engine coolant temperature condition:
• When the freeze frame data shows lower than 70 °C (158 °F), engine coolant temperature should be lower
than 70 °C (158 °F).
• When the freeze frame data shows higher than or equal to 70 °C (158 °F), engine coolant temperature should
be higher than or equal to 70 °C (158 °F).
NOTE:
• When the same malfunction is detected regardless of t he above vehicle conditions, reset the counter of driv-
ing pattern C.
• When the above conditions are satisfied without detecting t he same malfunction, reset the counter of driving
pattern C.
• The 1st trip DTC will be cleared when C counter is c ounted once without the same malfunction after DTC is
stored in ECM.
DRIVING PATTERN D
Driving pattern D means a trip satisfying the following conditions.
• The state of driving at 40 km/h (25 MPH) reaches 300 seconds or more in total.
• Idle speed lasts 30 seconds or more.
• A lapse of 600 seconds or more after engine start.
NOTE:
• When the same malfunction is detected regardless of driv ing conditions, reset the counter of driving pattern
D.
• When the above conditions are satisfied without detecting t he same malfunction, reset the counter of driving
pattern D.
DIAGNOSIS DESCRIPTION : System Readiness Test (SRT) CodeINFOID:0000000009462537
System Readiness Test (SRT) code is spec ified in Service $01 of SAE J1979/ISO 15031-5.
As part of an enhanced emissions test for Inspection & Ma intenance (I/M), certain states require the status of
SRT be used to indicate whether the ECM has completed self-diagnosis of major emission systems and com-
ponents. Completion must be verified in order for the emissions inspection to proceed.
If a vehicle is rejected for a State emissions inspec tion due to one or more SRT items indicating “INCMP”, use
the information in this Service Manual to set the SRT to “CMPLT”.
In most cases the ECM will automatically complete its self-diagnosis cycle during normal usage, and the SRT
status will indicate “CMPLT” for each application system . Once set as “CMPLT”, the SRT status remains
“CMPLT” until the self-diagnosis memory is erased.
Occasionally, certain portions of the self-diagnostic test may not be completed as a result of the customer's
normal driving pattern; the SRT will indicate “INCMP” for these items.
NOTE:
The SRT will also indicate “INCMP” if the self-diagnosis memory is erased for any reason or if the ECM mem-
ory power supply is interrupted for several hours.
If, during the state emissions inspection, the SRT indica tes “CMPLT” for all test items, the inspector will con-
tinue with the emissions test. However, if the SRT indi cates “INCMP” for one or more of the SRT items the
vehicle is returned to the customer untested.
NOTE:
If permanent DTC is stored or MIL illuminates during t he state emissions inspection, the vehicle is alsore-
turned to the customer untested even though the SRT indicate s “CMPLT” for all test items. Therefore, it isim-
portant to check SRT (“CMPLT”), DTC (No DT Cs) and permanent DTC (NO permanent DTCs) before
theinspection.
SRT SET TIMING
SRT is set as “CMPLT” after self-diagnosis has been performed one or more times. Completion of SRT is
done regardless of whether the result is OK or NG. T he set timing is different between OK and NG results and
is shown in the table below.
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