Page 1683 of 3502
![NISSAN TEANA 2003 Service Manual TROUBLE DIAGNOSIS
EC-401
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Fail-Safe ChartBBS004Y8
When the DTC listed below is detected, the ECM enters fail-safe mode and the MI lights up.
When there is an open circ NISSAN TEANA 2003 Service Manual TROUBLE DIAGNOSIS
EC-401
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Fail-Safe ChartBBS004Y8
When the DTC listed below is detected, the ECM enters fail-safe mode and the MI lights up.
When there is an open circ](/manual-img/5/57392/w960_57392-1682.png)
TROUBLE DIAGNOSIS
EC-401
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Fail-Safe ChartBBS004Y8
When the DTC listed below is detected, the ECM enters fail-safe mode and the MI lights up.
When there is an open circuit on MI circuit, the ECM cannot warn the driver by lighting up MI when there
is malfunction on engine control system.
Therefore, when electrical controlled throttle and part of ECM related diagnoses are continuously detected
as NG for 5 trips, ECM warns the driver that engine control system malfunctions and MI circuit is open by
means of operating fail-safe function.
The fail-safe function also operates when above diagnoses except MI circuit are detected and demands
the driver to repair the malfunction.
DTC No. Detected items Engine operating condition in fail-safe mode
P0102
P0103Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.
P0122
P0123
P0222
P0223
P2135Throttle position sensor The ECM controls the electric throttle control actuator in regulating 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.
P1121 Electric throttle control
actuator(When electric throttle control actuator does not function properly due to the return spring
malfunction:)
ECM controls the electric throttle actuator by regulating the throttle opening around the
idle position. The engine speed will not rise more than 2,000 rpm.
(When throttle valve opening angle in fail-safe mode is not in specified range:)
ECM controls the electric throttle control actuator by regulating the throttle opening to 20
degrees or less.
(When ECM detects the throttle valve is stuck open:)
While the vehicle is driving, it slows down gradually by fuel cut. After the vehicle stops,
the engine stalls.
The engine can restart in P or N position, and engine speed will not exceed 1,000 rpm or
more.
P1122 Electric throttle control
functionECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P1124
P1126Throttle control motor relay ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P1128 Throttle control motor ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P1229 Sensor power supply ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P1805 Brake switch ECM controls the electric throttle control actuator by regulating the throttle opening to a
small range.
Therefore, acceleration will be poor.
Vehicle condition Driving condition
When engine is idling Normal
When accelerating Poor acceleration
P2122
P2123
P2127
P2128
P2138Accelerator pedal position
sensorThe ECM controls the electric throttle control actuator in regulating 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.
Engine operating condition in fail-safe mode Engine speed will not rise more than 2,500 rpm due to the fuel cut
Page 1684 of 3502
![NISSAN TEANA 2003 Service Manual EC-402
[VQ]
TROUBLE DIAGNOSIS
Symptom Matrix ChartBBS004Y9
SYSTEM — BASIC ENGINE CONTROL SYSTEM
SYMPTOM
Refer-
ence page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
NISSAN TEANA 2003 Service Manual EC-402
[VQ]
TROUBLE DIAGNOSIS
Symptom Matrix ChartBBS004Y9
SYSTEM — BASIC ENGINE CONTROL SYSTEM
SYMPTOM
Refer-
ence page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT](/manual-img/5/57392/w960_57392-1683.png)
EC-402
[VQ]
TROUBLE DIAGNOSIS
Symptom Matrix ChartBBS004Y9
SYSTEM — BASIC ENGINE CONTROL SYSTEM
SYMPTOM
Refer-
ence page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Fuel pump circuit 11232 22 3 2EC-690
Fuel pressure regulator system334444444 4EC-392
Fuel injector circuit 11232 22 2EC-684
Evaporative emission system 334444444 4EC-366
Air Positive crankcase ventilation sys-
tem
334444444 41EC-370
Incorrect idle speed adjustment 1 1 1 1 1EC-381
Electric throttle control actuator 112332222 2 2EC-552,
EC-555
IgnitionIncorrect ignition timing adjustment 33111 11 1EC-381
Ignition circuit 11222 22 2EC-735
Main power supply and ground circuit22333 33 23EC-451
Mass air flow sensor circuit
1
122
222 2EC-466
Engine coolant temperature sensor circuit
333EC-474
Heated oxygen sensor 1 circuitEC-486
,
EC-496
,
EC-696
Throttle position sensor circuit
22EC-479
,
EC-505
,
EC-586
,
EC-588
,
EC-645
Accelerator pedal position sensor circuit 3 2 1EC-590
,
EC-631
,
EC-638
,
EC-652
Knock sensor circuit 2 3EC-512
Crankshaft position sensor (POS) circuit 2 2EC-517
Camshaft position sensor (PHASE) circuit 3 2EC-524
Vehicle speed signal circuit 2 3 3 3EC-762
Power steering pressure sensor circuit 2 3 3EC-533
ECM 22333333333EC-538,
EC-541
Page 1685 of 3502
![NISSAN TEANA 2003 Service Manual TROUBLE DIAGNOSIS
EC-403
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1 - 6: The numbers refer to the order of inspection.
(continued on next page)
SYSTEM — ENGINE MECHANICAL & OTHER
Intake valve timing control NISSAN TEANA 2003 Service Manual TROUBLE DIAGNOSIS
EC-403
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1 - 6: The numbers refer to the order of inspection.
(continued on next page)
SYSTEM — ENGINE MECHANICAL & OTHER
Intake valve timing control](/manual-img/5/57392/w960_57392-1684.png)
TROUBLE DIAGNOSIS
EC-403
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1 - 6: The numbers refer to the order of inspection.
(continued on next page)
SYSTEM — ENGINE MECHANICAL & OTHER
Intake valve timing control solenoid valve cir-
cuit32 13223 3EC-545
PNP switch circuit 3 3 3 3 3EC-614
VIAS control solenoid valve circuit 1EC-753
Refrigerant pressure sensor circuit 2 3 3 4EC-748
Electrical load signal circuit 3EC-670
Air conditioner circuit 223333333 3 2AT C - 3 4
ABS actuator and electric unit (control unit) 4BRC-8 or
BRC-44
SYMPTOM
Refer-
ence page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Fuel tank
5
5FL-8
Fuel piping 5 5 5 5 5 5FL-3
Vapor lock—
Valve deposit
5 555 55 5—
Poor fuel (Heavy weight gaso-
line, Low octane)—
Page 1686 of 3502
![NISSAN TEANA 2003 Service Manual EC-404
[VQ]
TROUBLE DIAGNOSIS
Air Air duct
55555 5EM-131
Air cleanerEM-131
Air leakage from air duct
(Mass air flow sensor — electric
throttle control actuator)
5555EM-131
Electric throttle contr NISSAN TEANA 2003 Service Manual EC-404
[VQ]
TROUBLE DIAGNOSIS
Air Air duct
55555 5EM-131
Air cleanerEM-131
Air leakage from air duct
(Mass air flow sensor — electric
throttle control actuator)
5555EM-131
Electric throttle contr](/manual-img/5/57392/w960_57392-1685.png)
EC-404
[VQ]
TROUBLE DIAGNOSIS
Air Air duct
55555 5EM-131
Air cleanerEM-131
Air leakage from air duct
(Mass air flow sensor — electric
throttle control actuator)
5555EM-131
Electric throttle control actuatorEM-133
Air leakage from intake manifold/
Collector/GasketEM-133,
EM-138
Cranking Battery
111111
11SC-4
Generator circuitSC-27
Starter circuit 3EM-228
Signal plate 6EM-228
PNP switch 4AT- 2 3 0,
CVT-62
Engine Cylinder head
55555 55 5EM-210
Cylinder head gasket 4 3
Cylinder block
66666 66 64
EM-228
Piston
Piston ring
Connecting rod
Bearing
Crankshaft
Va l v e
mecha-
nismTiming chain
55555 55 5EM-173
CamshaftEM-192
Intake valve timing controlEM-173
Intake valve
3EM-210
Exhaust valve
Exhaust Exhaust manifold/Tube/Muffler/
Gasket
55555 55 5EM-140
,
EX-2
Three way catalyst
Lubrica-
tionOil pan/Oil strainer/Oil pump/Oil
filter/Oil gallery/Oil cooler
55555 55 5EM-145
,
LU-22
, LU-
23 , LU-25
Oil level (Low)/Filthy oilLU-19
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Page 1688 of 3502
EC-406
[VQ]
TROUBLE DIAGNOSIS
Engine Control Component Parts LocationBBS004YA
PBIB2473E
Page 1698 of 3502
![NISSAN TEANA 2003 Service Manual EC-416
[VQ]
TROUBLE DIAGNOSIS
2OHeated oxygen sensor 1
heater (Bank 1)[Engine is running]
Warm-up condition
Engine speed: Below 3,600 rpmApproximately 8V
[Engine is running]
Warm-up condition
E NISSAN TEANA 2003 Service Manual EC-416
[VQ]
TROUBLE DIAGNOSIS
2OHeated oxygen sensor 1
heater (Bank 1)[Engine is running]
Warm-up condition
Engine speed: Below 3,600 rpmApproximately 8V
[Engine is running]
Warm-up condition
E](/manual-img/5/57392/w960_57392-1697.png)
EC-416
[VQ]
TROUBLE DIAGNOSIS
2OHeated oxygen sensor 1
heater (Bank 1)[Engine is running]
Warm-up condition
Engine speed: Below 3,600 rpmApproximately 8V
[Engine is running]
Warm-up condition
Engine speed: Above 3,600 rpmBATTERY VOLTAGE
(11 - 14V)
3G/WThrottle control motor relay
power supply[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)
4 L Throttle control motor (Close)[Ignition switch: ON]
Engine: Stopped
Shift lever: D
Accelerator pedal: Fully releasedApproximately 2.1V
5 Y Throttle control motor (Open)[Ignition switch: ON]
Engine: Stopped
Shift lever: D
Accelerator pedal: Fully depressedApproximately 3V
6R/LHeated oxygen sensor 2
heater (Bank 2)[Engine is running]
Engine speed: Below 3,600 rpm after the
following conditions are met
–Engine: After warming up
–Keeping the engine speed between 3,500
and 4,000 rpm for 1 minute and at idle for 1
minute under no load0 - 1.0V
[Ignition switch: ON]
Engine: Stopped
[Engine is running]
Engine speed: Above 3,600 rpmBATTERY VOLTAGE
(11 - 14V)
8W/LElectronic controlled engine
mount-1[Engine is running]
Idle speed (with vehicle stopped)0 - 3.0V
[Engine is running]
Except above conditionsBATTERY VOLTAGE
(11 - 14V)
9O/BElectronic controlled engine
mount-2[Engine is running]
Idle speed (with vehicle stopped)BATTERY VOLTAGE
(11 - 14V)
[Engine is running]
Except above conditions0 - 3.0V TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
PBIB0519E
PBIB1104E
PBIB1105E
Page 1699 of 3502
TROUBLE DIAGNOSIS
EC-417
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EC
10 YIntake valve timing control
solenoid valve (Bank 2)[Engine is running]
Warm-up condition
Idle speedBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
Warm-up condition
When revving engine up to 2,000 rpm
quickly7 - 12V
11 LG/BIntake valve timing control
solenoid valve (Bank 1)[Engine is running]
Warm-up condition
Idle speedBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
Warm-up condition
When revving engine up to 2,000 rpm
quickly7 - 12V
12 WPower steering pressure sen-
sor[Engine is running]
Steering wheel: Being turned0.5 - 4.5V
[Engine is running]
Steering wheel: Not being turned0.4 - 0.8V
13 WCrankshaft position sensor
(POS)[Engine is running]
Warm-up condition
Idle speed
NOTE:
The pulse cycle changes depending on rpm
at idleApproximately 1.6V
[Engine is running]
Engine speed: 2,000 rpmApproximately 1.4V TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
PBIB1790E
PBIB1790E
PBIB1041E
PBIB1042E
Page 1701 of 3502
![NISSAN TEANA 2003 Service Manual TROUBLE DIAGNOSIS
EC-419
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25 P/BHeated oxygen sensor 2
heater (Bank 1)[Engine is running]
Engine speed: Below 3,600 rpm after the
following conditions are met
–Eng NISSAN TEANA 2003 Service Manual TROUBLE DIAGNOSIS
EC-419
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25 P/BHeated oxygen sensor 2
heater (Bank 1)[Engine is running]
Engine speed: Below 3,600 rpm after the
following conditions are met
–Eng](/manual-img/5/57392/w960_57392-1700.png)
TROUBLE DIAGNOSIS
EC-419
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EC
25 P/BHeated oxygen sensor 2
heater (Bank 1)[Engine is running]
Engine speed: Below 3,600 rpm after the
following conditions are met
–Engine: After warming up
–Keeping the engine speed between 3,500
and 4,000 rpm for 1 minute and at idle for 1
minute under no load0 - 1.0V
[Ignition switch: ON]
Engine: Stopped
[Engine is running]
Engine speed: Above 3,600 rpmBATTERY VOLTAGE
(11 - 14V)
29 Y/G VIAS control solenoid valve[Engine is running]
Idle speedBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
Engine speed:
Between 1,800 and 3,600 rpm (VQ35DE
engine)
Between 1,800 and 3,750 rpm (VQ23DE
engine)0 - 1.0V
33 WCamshaft position sensor
(PHASE) (Bank 1)[Engine is running]
Warm-up condition
Idle speed
NOTE:
The pulse cycle changes depending on rpm
at idle1.0 - 4.0V
[Engine is running]
Engine speed: 2,000 rpm1.0 - 4.0V
34 L/Y Intake air temperature sensor[Engine is running]Approximately 0 - 4.8V
Output voltage varies with intake
air temperature.
35 WHeated oxygen sensor 1
(Bank 1)[Engine is running]
Warm-up condition
Engine speed: 2,000 rpm0 - Approximately 1.0V
(Periodically change) TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
PBIB1039E
PBIB1040E