EC-42
< SYSTEM DESCRIPTION >[QR25DE]
SYSTEM
Fail Safe Pattern
Fail Safe List
× :Applicable —: Not applicable
Fail safe mode Vehicle behavior
Traveling con-
trol mode Accelerator an-
gle variation
control ECM controls the accelerator pedal depression speed to make it slower than actual speed. This
causes a drop in accelerating performance and encourages the driver to repair malfunction.
NOTE:
ECM does not control the accelerator pedal releasing speed.
Engine output
control ECM reduces the engine output, according to the rise in engine speed. This reduces the vehicle
speed to encourage the driver to repair malfunction.
Device fix mode • This mode fixes the IVT control solenoid valve and the EVT control solenoid valve in the refer-
ence position.
• The intake manifold runner control valve motor is turned OFF (intake manifold runner control valve opens).
Pattern Fail safe mode
A Traveling control mode Accelerator angle variation control
B Engine output control
C Device fix mode
DTC No. Detected items Vehicle behavior
Pattern Others
ABC
P0011 Intake valve timing control ——×ECM activates the IVT intermediate lock control solenoid
valve to bring the cam sprocket into an intermediate lock con-
dition.
P0014
P0078 Exhaust valve timing control
——× —
P0101
P0102
P0103 Mass air flow sensor circuit
××× —
P0122
P0123
P0222
P0223
P2135 Throttle position sensor
———The ECM controls the electric throttle control actuator in reg-
ulating the throttle opening in order for the idle position to be
within +10 degrees.
The ECM regulates the opening speed of the throttle valve to
be slower than the normal condition.
So, the acceleration will be poor.
P0171
P0172 Fuel injection system
×—— —
P0197
P0198 Engine oil temperature sensor
———Exhaust valve timing control does not function.
P0300
P0301
P0302
P0303
P0304 Misfire
×—— —
P0500 Vehicle speed sensor ×—— —
P050A Cold start control ×—— —
P0524 Engine oil pressure
———• ECM illuminates oil pressure warning lamp on the combina-
tion meter.
• Engine speed will not rise more than 4,000rpm due to the
fuel cut.
• Fail-safe is canceled when ignition switch OFF → ON.
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EC-48
< SYSTEM DESCRIPTION >[QR25DE]
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-51
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The intake valve timing intermediate lock control improv
es the cleaning ability of exhaust gas at cold starting
by fixing the camshaft sprocket (INT) with two lock keys and bringing the cam phase into intermediate phase.
Cam phase is fixed at the intermediate phase by two lock keys in the camshaft sprocket (INT). Lock key 1 con-
trols retard position and lock key 2 controls advance position.
ECM controls the intermediate phase lock by opening/clos ing the intake valve timing intermediate lock control
solenoid valve to control oil pressure acti ng on the lock key and locking/unlocking the lock key.
Lock/Unlock Activation
When ECM activates the intake valve timing intermediate lock control solenoid valve, oil pressure generated in
the oil pump is drained through the oil pressure path in t he control valve. Since oil pressure is not acted on the
lock key, the lock key position is fixed by the spri ng tension and the cam phase is fixed at the intermediate
phase.
When ECM deactivates the intake valve timing intermediate lock control solenoid valve, unlocking oil pressure
acts on each lock key. Lock key 1 is not released because it is under load due to sprocket rotational force. For
this reason, lock key 2 is released first by being pushed up by unlocking oil pressure. When lock key 2 is
released, some clearance is formed between lock key 1 and the rotor due to sprocket rotational force and
return spring force. Accordingly, lock key 1 is pushed up by unlocking oil pressure and the intermediated
phase lock is released.
When stopping the engine
When the ignition switch is turned from idle state to OFF, ECM receives an ignition switch signal from BCM via
CAN communication and activates the intake valve timing intermediate lock control solenoid valve and drains
oil pressure acting on the lock key before activating the intake valve timing control solenoid valve and operat-
ing the cam phase toward the advance position.
The cam phase is fixed by the lock key when shifting to the intermediated phase and ECM performs Lock
judgment to stop the engine.
When starting the engine
JPBIA6317GB
JPBIA5970GB
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EC-52
< SYSTEM DESCRIPTION >[QR25DE]
SYSTEM
When starting the engine by cold start, ECM judges the
locked/unlocked state when ignition switch is turned
ON. When judged as locked state (fixed at the intermedi ate phase), the intake valve timing intermediate lock
control solenoid valve is activated. Since oil pre ssure does not act on the lock key even when the engine is
started, the cam phase is fixed at the intermediate phas e and the intake valve timing control is not performed.
When the engine stops without locking the cam phase at the intermediate phase due to an engine stall and the
state is not judged as locked, the intake valve timing intermediate lock control solenoid valve and the intake
valve timing control solenoid valve are activated and the cam phase shifts to the advanced position to be
locked at the intermediate phase. Even when not locked in the intermediate lock phase due to no oil pressure
or low oil pressure, a ratchet structure of the camshaft sprocket (INT) rotor allows the conversion to the inter-
mediate phase in stages by engine vibration.
When engine coolant temperature is more than 60 °C, the intake valve timing is controlled by deactivating the
intake valve timing intermediate lock control so lenoid valve and releasing the intermediate phase lock.
When the engine is started after warming up, ECM releas es the intermediate phase lock immediately after the
engine start and controls the intake valve timing.
EXHAUST VALVE TIMING CONTROL
EXHAUST VALVE TIMING CONT ROL : System DescriptionINFOID:0000000009462097
SYSTEM DIAGRAM
INPUT/OUTPUT SIGNAL CHART
JPBIA4761GB
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed and piston position
Exhaust valve
timing control Exhaust valve timing control
solenoid valve
Camshaft position sensor (PHASE)
Engine oil temperature sensor Engine oil temperature
Exhaust valve timing control position
sensor Exhaust valve timing signal
Combination meter CAN commu-
nication Vehicle speed signal
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DIAGNOSIS SYSTEM (ECM)EC-71
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Explanation for Driving Patterns Except for “Misfire
System”
Driving Pattern A
Refer to EC-71, "DIAGNOSIS DESCRIPTION : Driving Pattern".
Driving Pattern B
Refer to EC-71, "DIAGNOSIS DESCRIPTION : Driving Pattern".
DIAGNOSIS DESCRIPTION : Driving PatternINFOID:0000000009462115
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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DIAGNOSIS SYSTEM (ECM)EC-73
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OK: Self-diagnosis is carried out and the result is OK.
NG: Self-diagnosis is carried out and the result is NG.
—: Self-diagnosis is not carried out.
When all SRT related self-diagnoses show OK results in a single cycle (Ignition OFF-ON-OFF), the SRT will
indicate “CMPLT”. → Case 1 above
When all SRT related self-diagnoses show OK results through several different cycles, the SRT will indicate
“CMPLT” at the time the respective se lf-diagnoses have at least one OK result. → Case 2 above
If one or more SRT related self-diagnoses show NG resu lts in 2 consecutive cycles, the SRT will also indicate
“CMPLT”. → Case 3 above
The table above shows that the minimum number of cycles for setting SRT as “INCMP” is the number one (1)
for each self-diagnosis (Case 1 & 2) or the number two (2) for one of self-diagnoses (Case 3). However, in
preparation for the state emissions inspection, it is unnecessary for each self-diagnosis to be executed twice
(Case 3) for the following reasons:
• The SRT will indicate “CMPLT” at the time the respective self-diagnoses have one (1) OK result.
• The emissions inspection requires “CMPLT” of the SRT only with OK self-diagnosis results.
• During SRT driving pattern, the 1st trip DTC (NG) is detected prior to “CMPLT” of SRT and the self-diagnosis
memory must be erased from the ECM after repair.
• If the 1st trip DTC is erased, all the SRT will indicate “INCMP”. NOTE:
SRT can be set as “CMPLT” together with the DTC(s) . Therefore, DTC check must always be carried out
prior to the state emission inspection even though the SRT indicates “CMPLT”.
DIAGNOSIS DESCRIPTION : Permanent Di agnostic Trouble Code (Permanent DTC)
INFOID:0000000009462117
Permanent DTC is defined in SAE J1979/ISO 15031-5 Service $0A.
ECM stores a DTC issuing a command of turning on MIL as a permanent DTC and keeps storing the DTC as
a permanent DTC until ECM judges that there is no presence of malfunction.
Permanent DTCs cannot be erased by using the erase f unction of CONSULT or Generic Scan Tool (GST) and
by disconnecting the battery to shut off power to ECM. This prevents a vehicle from passing the in-use inspec-
tion without repairing a malfunctioning part.
When not passing the in-use inspection due to more than one permanent DTC, permanent DTCs should be
erased, referring to this manual.
NOTE:
• The important items in in-use inspection are that MIL is not ON, SRT test items are set, and permanent
DTCs are not included.
• Permanent DTCs do not apply for regions that permanent DTCs are not regulated by law.
Self-diagnosis result Example
Diagnosis Ignition cycle
← ON →OFF ← ON →OFF ← ON →OFF ← ON →
All OK Case 1 P0400 OK (1) — (1) OK (2) — (2) P0402 OK (1) — (1) — (1) OK (2)
P1402 OK (1) OK (2) — (2) — (2)
SRT of EGR “CMPLT” “CMPLT” “CMPLT” “CMPLT”
Case 2 P0400 OK (1) — (1) — (1) — (1) P0402 — (0) — (0) OK (1) — (1)
P1402 OK (1) OK (2) — (2) — (2)
SRT of EGR “INCMP” “INCMP” “CMPLT” “CMPLT”
NG exists Case 3 P0400 OK OK — — P0402 — — — —
P1402 NG — NG NG
(Consecutive
NG)
(1st trip) DTC 1st trip DTC — 1st trip DTC
DTC
(= MIL ON)
SRT of EGR “INCMP” “INCMP” “INCMP” “CMPLT”
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EC-74
< SYSTEM DESCRIPTION >[QR25DE]
DIAGNOSIS SYSTEM (ECM)
PERMANENT DTC SET TIMING
The setting timing of permanent DTC is stored in EC
M with the lighting of MIL when a DTC is confirmed.
DIAGNOSIS DESCRIPTION : Malfunction Indicator Lamp (MIL)INFOID:0000000009462118
When emission-related ECU detects a malfunction in the emission
control systems components and/or the powertrain control compo-
nents (which affect vehicle emissions), it turns on/blinks MIL to
inform the driver that a malfunction has been detected.
1. The MIL illuminates when ignition switch is turned ON (engine is not running).
NOTE:
Check the MIL circuit if MIL does not illuminate. Refer to EC-
517, "Diagnosis Procedure".
2. When the engine is started, the MIL should go off.
NOTE:
If MIL continues to illuminate/blink, perform self-diagnoses and
inspect/repair accordingly because an emission-rela ted ECU has detected a malfunction in the emission
control systems components and/or the powertrain cont rol components (which affect vehicle emissions).
On Board Diagnosis FunctionINFOID:0000000009462119
ON BOARD DIAGNOSIS ITEM
The on board diagnostic system has the following functions.
BULB CHECK MODE
Description
This function allows damage inspection in the MIL bulb (blown, open circuit, etc.).
Operation Procedure
1. Turn ignition switch ON.
2. The MIL on the instrument panel should stay ON. If it remains OFF, check MIL circuit. Refer to EC-517, "Diagnosis Procedure"
.
SRT STATUS MODE
Description
This function allows to read if ECM has completed t he self-diagnoses of major emission control systems and
components. For SRT, refer to EC-72, "DIAGNOSIS DESCRIPTION : System Readiness Test (SRT) Code"
.
Operation Procedure
1. Turn ignition switch ON and wait 20 seconds.
2. SRT status is indicated as shown blow. • ECM continues to illuminate MIL if all SRT codes are set.
JSBIA1315ZZ
Diagnostic test mode Function
Bulb check MIL can be checked.
SRT status ECM can read if SRT codes are set.
Malfunction warning If ECM detects a malfunction, it illuminates or blinks MIL to inform the driver that a malfunction has been detected.
Self-diagnostic results DTCs or 1st trip DTCs stored in ECM can be read.
Accelerator pedal released po-
sition learning ECM can learn the accelerator pedal released position. Refer to
EC-177, "Work Procedure"
.
Throttle valve closed position
learning ECM can learn the throttle valve closed position. Refer to
EC-178, "Work Procedure"
.
Idle air volume learning ECM can learn the idle air volume. Refer to EC-179, "Work Procedure"
.
Mixture ratio self -learning value
clear Mixture ratio self-learning value can be erased. Refer to
EC-181, "Work Procedure"
.
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