2008 NISSAN TEANA Trans

DIAGNOSIS AND REPAIR WORKFLOW
EC-9
< BASIC INSPECTION >[VQ25DE, VQ35DE]
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YES >> GO TO 7.
NO >> GO TO 9.
7.PERFORM “SPEC” OF “DATA MONITOR” MODE
With CONSULT-III
Check that “MAS A/F SE-B1”, “B/FUEL SCHDL”, “A/F ALPHA-B1” and “A/F ALPHA-B2” are within the SP
value using CONSULT-III in “SPEC” of “DATA MONITOR” mode. Refer to EC-124, "
Component Function
Check".
Are they within the SP value?
YES >> GO TO 9.
NO >> GO TO 8.
8.DETECT MALFUNCTIONING PART BY TROUBLE DIAGNOSIS - SPECIFICATION VALUE
Detect malfunctioning part according to EC-125, "
Diagnosis Procedure".
Is a malfunctioning part detected?
YES >> GO TO 11.
NO >> GO TO 9.
9.DETECT MALFUNCTIONING SYSTEM BY SYMPTOM TABLE
Detect malfunctioning system according to EC-400, "
Symptom Table" based on the confirmed symptom in
step 4, and determine the trouble diagnosis order based on possible causes and symptoms.
>> GO TO 10.
10.DETECT MALFUNCTIONING PART BY DIAGNOSTIC PROCEDURE
Inspect according to Diagnostic Procedure of the system.
NOTE:
The Diagnostic Procedure in EC section described based on open circuit inspection. A short circuit inspection
is also required for the circuit check in the Diagnostic Procedure. For details, refer to “Circuit Inspection” in GI-
37, "Circuit Inspection".
Is a malfunctioning part detected?
YES >> GO TO 11.
NO >> Monitor input data from related sensors or check voltage of related ECM terminals using CON-
SULT-III. Refer to EC-357, "
Reference Value".
11 .REPAIR OR REPLACE THE MALFUNCTIONING PART
1. Repair or replace the malfunctioning part.
2. Reconnect parts or connectors disconnected during Diagnostic Procedure again after repair and replace-
ment.
3. Check DTC. If DTC is displayed, erase it, refer to EC-102, "
Diagnosis Description".
>> GO TO 12.
12.FINAL CHECK
When DTC was detected in step 2, perform DTC Confirmation Procedure or Overall Function Check again,
and then check that the malfunction have been completely repaired.
When symptom was described from the customer, refer to confirmed symptom in step 3 or 4, and check that
the symptom is not detected.
Is DTC detected and does symptom remain?
YES-1 >> DTC is detected: GO TO 10.
YES-2 >> Symptom remains: GO TO 6.
NO >> Before returning the vehicle to the customer, always erase unnecessary DTC in ECM and TCM
(Transmission Control Module). (Refer to EC-102, "
Diagnosis Description".) If the completion of
SRT is needed, drive vehicle under the specific DRIVING PATTERN in EC-392,
"HowtoSetSRTCode".

EC-16
< BASIC INSPECTION >[VQ25DE, VQ35DE]
INSPECTION AND ADJUSTMENT
THROTTLE VALVE CLOSED POSITION LEARNING
THROTTLE VALVE CLOSED POSITION LEARNING : DescriptionINFOID:0000000003856455
Throttle Valve Closed Position Learning is an operation to learn the fully closed position of the throttle valve by
monitoring the throttle position sensor output signal. It must be performed each time harness connector of
electric throttle control actuator or ECM is disconnected.
THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement
INFOID:0000000003856456
1.START
1. Check that accelerator pedal is fully released.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
Check that throttle valve moves during above 10 seconds by confirming the operating sound.
>> END
IDLE AIR VOLUME LEARNING
IDLE AIR VOLUME LEARNING : DescriptionINFOID:0000000003856457
Idle Air Volume Learning is a function of ECM to learn the idle air volume that keeps engine idle speed within
the specific range. It must be performed under the following conditions:
 Each time electric throttle control actuator or ECM is replaced.
 Idle speed or ignition timing is out of specification.
IDLE AIR VOLUME LEARNING : Special Repair RequirementINFOID:0000000003856458
1.PRECONDITIONING
Before performing Idle Air Volume Learning, check that all of the following conditions are satisfied.
Learning will be cancelled if any of the following conditions are missed for even a moment.
 Battery voltage: More than 12.9 V (At idle)
 Engine coolant temperature: 70 - 100°C (158 - 212°F)
 Selector lever: P or N
 Electric load switch: OFF
(Air conditioner, head lamp, rear window defogger)
-For vehicle equipped with daytime light systems, perform one of the following procedures before
starting engine not to illuminate headlamps.
 Apply parking brake
 Set lighting switch to the 1st position
 Steering wheel: Neutral (Straight-ahead position)
 Vehicle speed: Stopped
 Transmission: Warmed-up
- With CONSULT-III: Drive vehicle until “ATF TEMP SEN” in “DATA MONITOR” mode of “CVT” system indi-
cates less than 0.9 V.
- Without CONSULT-III: Drive vehicle for 10 minutes.
Will CONSULT-III be used?
YES >> GO TO 2.
NO >> GO TO 3.
2.PERFORM IDLE AIR VOLUME LEARNING
With CONSULT-III
1. Perform EC-15, "
ACCELERATOR PEDAL RELEASED POSITION LEARNING : Special Repair Require-
ment".
2. Perform EC-16, "
THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement".
3. Start engine and warm it up to normal operating temperature.
4. Select “IDLE AIR VOL LEARN” in “WORK SUPPORT” mode.
5. Touch “START” and wait 20 seconds.

EC-20
< FUNCTION DIAGNOSIS >[VQ25DE, VQ35DE]
ENGINE CONTROL SYSTEM
System Description
INFOID:0000000003856462
ECM performs various controls such as fuel injection control and ignition timing control.
Component Parts LocationINFOID:0000000003856463
1. Intake valve timing control solenoid
valve (bank 1)2. Intake valve timing control solenoid
valve (bank 2)3. Electronic controlled engine mount
control solenoid valve
4. Fuel injector (bank 2) 5. Cooling fan motor-2 6. A/F sensor 1 (bank 2)
7. Ignition coil (with power transistor)
and spark plug (bank 2)8. Camshaft position sensor (PHASE)
(bank 2)9. Crankshaft position sensor (POS)
10. Engine coolant temperature sensor 11. Cooling fan motor-1 12. ECM
13. Refrigerant pressure sensor 14. Battery current sensor 15. IPDM E/R
16. Mass air flow sensor (with intake air
temperature sensor)17. Electric throttle control actuator 18. Power valve actuator 2 (VQ35DE
models)
19. EVAP canister purge volume control
solenoid valve20. Camshaft position sensor (PHASE)
(bank 1)21. Ignition coil (with power transistor)
and spark plug (bank 1)
22. A/F sensor 1 (bank 1) 23. Fuel injector (bank 1) 24. VIAS control solenoid valve 1 and 2
(VQ35DE models)
25. Power valve actuator 1
JMBIA1373ZZ

ENGINE CONTROL SYSTEM
EC-21
< FUNCTION DIAGNOSIS >[VQ25DE, VQ35DE]
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1. Mass air flow sensor (with intake air
temperature sensor)2. Electric throttle control actuator
: Vehicle front
1. Ignition coil (with power transistor)
and spark plug (bank 1)2. Fuel injector (bank 1) 3. Fuel injector (bank 2)
4. Ignition coil (with power transistor)
and spark plug (bank 2)5. EVAP canister
: Vehicle front
1. Knock sensor (bank 1) 2. Knock sensor (bank 2) 3. Knock sensor
: Vehicle front
JMBIA1374ZZ
JMBIA1375ZZ
JMBIA1376GB
JMBIA1377ZZ

ENGINE CONTROL SYSTEM
EC-25
< FUNCTION DIAGNOSIS >[VQ25DE, VQ35DE]
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Component DescriptionINFOID:0000000003856464
1. Fuel level sensor unit and fuel pump
harness connector2. Fuel pressure regulator 3. Fuel level sensor unit and fuel pump
: Vehicle front
JMBIA1385ZZ
Component Reference
A/F sensor 1EC-163, "
Description"
A/F sensor 1 heaterEC-140, "Description"
Accelerator pedal position sensorEC-304, "Description"
ASCD brake switchEC-273, "Description"
ASCD steering switchEC-270, "Description"
Battery current sensorEC-258, "Description"
Camshaft position sensor (PHASE)EC-222, "Description"
Crankshaft position sensor (POS)EC-218, "Description"
Cooling fan motorEC-324, "Description"
Electric throttle control actuatorEC-302, "Description"
Electronic controlled engine mountEC-331, "Description"
Engine coolant temperature sensorEC-157, "Description"
EVAP canister purge volume control solenoid valveEC-231, "Description"
Fuel injectorEC-334, "Description"
Fuel pumpEC-337, "Description"
Heated oxygen sensor 2EC-178, "Description"
Heated oxygen sensor 2 heaterEC-143, "Description"
Ignition coil with power transistorEC-341, "Description"
Intake air temperature sensorEC-154, "Description"
Intake valve timing control solenoid valveEC-146, "Description"
Knock sensorEC-215, "Description"
Mass air flow sensorEC-149, "Description"
PCV valveEC-347, "Description"
Power steering pressure sensorEC-236, "Description"
Power valves 1 and 2EC-351, "Description"
Refrigerant pressure sensorEC-348, "Description"
Stop lamp switchEC-291, "Description"
TCM (VQ35DE engine)
Park/neutral position (PNP) switch (VQ25DE engine)EC-245, "Description"
Throttle control motorEC-300, "Description"

MULTIPORT FUEL INJECTION SYSTEM
EC-29
< FUNCTION DIAGNOSIS >[VQ25DE, VQ35DE]
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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 better reduce CO, HC and NOx emissions. This system uses A/F sen-
sor 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 A/F sensor 1, refer to
EC-163, "
Description". This maintains the mixture ratio within the range of stoichiometric (ideal air-fuel mix-
ture).
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 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 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 controls the basic mixture ratio as close to the theoret-
ical mixture ratio as possible. However, the basic mixture 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 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 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 carried out over time to compensate for continual deviation
of the short-term fuel trim from the central value. Continual deviation will occur due to individual engine differ-
ences, wear over time and changes in the usage environment.
PBIB3020E

EC-30
< FUNCTION DIAGNOSIS >[VQ25DE, VQ35DE]
MULTIPORT FUEL INJECTION SYSTEM
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 six cylinders twice each engine cycle. In other words, pulse signals of
the same width are simultaneously transmitted from the ECM.
The six injectors will then receive the signals 2 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.
SEF179U

MULTIPORT FUEL INJECTION SYSTEM
EC-31
< FUNCTION DIAGNOSIS >[VQ25DE, VQ35DE]
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Component Parts LocationINFOID:0000000003857771
1. Intake valve timing control solenoid
valve (bank 1)2. Intake valve timing control solenoid
valve (bank 2)3. Electronic controlled engine mount
control solenoid valve
4. Fuel injector (bank 2) 5. Cooling fan motor-2 6. A/F sensor 1 (bank 2)
7. Ignition coil (with power transistor)
and spark plug (bank 2)8. Camshaft position sensor (PHASE)
(bank 2)9. Crankshaft position sensor (POS)
10. Engine coolant temperature sensor 11. Cooling fan motor-1 12. ECM
13. Refrigerant pressure sensor 14. Battery current sensor 15. IPDM E/R
16. Mass air flow sensor (with intake air
temperature sensor)17. Electric throttle control actuator 18. Power valve actuator 2 (VQ35DE
models)
19. EVAP canister purge volume control
solenoid valve20. Camshaft position sensor (PHASE)
(bank 1)21. Ignition coil (with power transistor)
and spark plug (bank 1)
22. A/F sensor 1 (bank 1) 23. Fuel injector (bank 1) 24. VIAS control solenoid valve 1 and 2
(VQ35DE models)
25. Power valve actuator 1
JMBIA1373ZZ