TROUBLE DIAGNOSISEC-91
< SERVICE INFORMATION > [VQ35DE]
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2.CHECK DTC*1
1. Check DTC*1.
2. Perform the following procedure if DTC*
1 is displayed.
- Record DTC*
1 and freeze frame data*2. (Print them out with CONSULT-III or GST.)
- Erase DTC*
1. (Refer to EC-55, "Emission-Related Diagnostic Information".)
- Study the relationship between the cause detected by DTC*
1 and the symptom described by the cus-
tomer. (Symptom Matrix Chart is useful. Refer to EC-96, "
Symptom Matrix Chart".)
3. Check related service bulletins for information.
Is any symptom described and any DTC detected?
Symptom is described, DTC*1 is displayed>>GO TO 3.
Symptom is described, DTC*
1 is not displayed>>GO TO 4.
Symptom is not described, DTC*
1 is displayed>>GO TO 5.
3.CONFIRM THE SYMPTOM
Try to confirm the symptom described by the customer (except MIL ON).
DIAGNOSIS WORK SHEET is usef ul to verify the incident.
Connect CONSULT-III to the vehicle and check diagnosis results.
Verify relation between the symptom and t he condition when the symptom is detected.
>> GO TO 5.
4.CONFIRM THE SYMPTOM
Try to confirm the symptom described by the customer.
DIAGNOSIS WORK SHEET is usef ul to verify the incident.
Connect CONSULT-III to the vehicle and check diagnosis results.
Verify relation between the symptom and t he condition when the symptom is detected.
>> GO TO 6.
5.PERFORM DTC CONFIRMATION PROCEDURE
Perform DTC Confirmation Procedure for the displayed DTC*
1, and then make sure that DTC*1 is detected
again.
If two or more DTCs*
1 are detected, refer to EC-93, "DTC Inspection Priority Chart" and determine trouble
diagnosis order.
NOTE:
Freeze frame data*
2 is useful if the DTC*1 is not detected.
Perform Overall Function Check if DTC Confirma tion Procedure is not included on Service Manual. This
simplified check procedure is an effective alternative though DTC*
1 cannot be detected during this check.
If the result of Overall Function Check is NG, it is the same as the detection of DTC*
1 by DTC Confirmation
Procedure.
Is DTC*
1 detected?
Yes >> GO TO 10.
No >> Check according to EC-139
.
6.PERFORM BASIC INSPECTION
Perform EC-80, "
Basic Inspection"
With CONSULT-III>>GO TO 7.
Without CONSULT-III>>GO TO 9.
7.PERFORM SPEC IN DATA MONITOR MODE
With CONSULT-III
Make sure that “MAS A/F SE-B1”, “B/FUEL SCHDL”, and “A/F ALPHA-B1”, “A/F ALPHA-B2” are within the SP
value using CONSULT-III “SPEC” in “DATA MONITOR” mode. Refer to EC-131, "
Diagnosis Procedure".
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TROUBLE DIAGNOSISEC-93
< SERVICE INFORMATION > [VQ35DE]
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There are many operating conditions that lead to the malfunction of
engine components. A good grasp of such conditions can make trou-
bleshooting faster and more accurate.
In general, each customer feels differently about a incident. It is
important to fully understand the symptoms or conditions for a cus-
tomer complaint.
Utilize a diagnostic worksheet like the one on the next page in order
to organize all the information for troubleshooting.
Some conditions may cause the MI
L to come on steady or blink and
DTC to be detected. Examples:
Vehicle ran out of fuel, which caused the engine to misfire.
Fuel filler cap was left off or incorrectly screwed on, allowing fuel to evaporate into the atmosphere.
Worksheet Sample
DTC Inspection Priority ChartINFOID:0000000001325928
If some DTCs are displayed at the same time, per form inspections one by one based on the following priority
chart.
NOTE:
SEF907L
MTBL0017
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EC-94
< SERVICE INFORMATION >[VQ35DE]
TROUBLE DIAGNOSIS
If DTC U1000 or U1001 is displayed with other DT C, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-146
.
If DTC U1010 is displayed with other DTC, fi rst perform the trouble diagnosis for DTC U1010.
Refer to EC-148
.
*: Models with ICC.Priority Detected items (DTC)
1 U1000 U1001 CAN communication line U1010 CAN communication
P0101 P0102 P0103 Mass air flow sensor
P0112 P0113 P0127 Intake air temperature sensor
P0117 P0118 P0125 Engine coolant temperature sensor
P0128 Thermostat function
P0122 P0123 P0222 P0223 P1225 P1226 P2135 Throttle position sensor
P0181 P0182 P0183 Fuel tank temperature sensor
P0327 P0328 Knock sensor
P0335 Crankshaft position sensor (POS)
P0340 P0345 Camshaft position sensor (PHASE)
P0460 P0461 P0462 P0463 Fuel level sensor
P0500 Vehicle speed sensor
P0605 ECM
P0643 Sensor power supply
P0700 TCM
P0705 Park/neutral position (PNP) switch
P0850 Park/neutral position (PNP) switch
P1610 - P1615 NATS
P2122 P2123 P2127 P2128 P2138 Accelerator pedal position sensor
2 P0031 P0032 P0051 P0052 Air fuel ratio (A/F) sensor 1 heater P0037 P0038 P0057 P0058 Heated oxygen sensor 2 heater
P0075 P0081 Intake valve timing control solenoid valve
P0130 P0131 P0132 P0133 P0150 P0151 P0152 P0153 P2A00 P2A03 Air fuel ratio (A/F) sensor 1
P0137 P0138 P0139 P0157 P0158 P0159 Heated oxygen sensor 2
P0441 EVAP control system purge flow monitoring
P0443 P0444 P0445 EVAP canister purge volume control solenoid valve
P0447 P0448 EVAP canister vent control valve
P0451 P0452 P0453 EVAP control system pressure sensor
P0550 Power steering pressure sensor
P0603 ECM power supply
P0710 P0717 P0720 P0731 P0732 P0733 P0734 P0735 P0740 P0744 P0745 P1730 P1752 P1757 P1762 P1767
P1772 P1774 A/T related sensors, solenoid valves and switches
P1217 Engine over temperature (OVERHEAT)
P1805 Brake switch
P2100 P2103 P2118 Electric throttle control actuator
P2101 Electric throttle control function
3 P0011 P0021 Intake valve timing control P0171 P0172 P0174 P0175 Fuel injection system function
P0300 - P0306 Misfire
P0420 P0430 Three way catalyst function
P0442 EVAP control system (SMALL LEAK)
P0455 EVAP control system (GROSS LEAK)
P0456 EVAP control sys tem (VERY SMALL LEAK)
P0506 P0507 Idle speed control system
P1148 P1168 Closed loop control
P1211 TCS control unit
P1212 TCS communication line
P1421 COLD START CONTROL
P1564 ICC steering switch/ASCD steering switch
P1568 ICC command valve*
P1572 ICC brake switch/ASCD brake switch
P1574 ICC vehicle speed sensor/ASCD vehicle speed sensor
P1715 Turbine revolution sensor
P2119 Electric throttle control actuator
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TROUBLE DIAGNOSISEC-95
< SERVICE INFORMATION > [VQ35DE]
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Fail-Safe ChartINFOID:0000000001325929
When the DTC listed below is detected, the EC
M enters fail-safe mode and the MIL lights up.
When there is an open circuit on MIL circuit, the ECM c annot warn the driver by MIL lighting up when there
is malfunction on engine control system.
Therefore, when electrical controlled throttle and pa rt of ECM related diagnoses are continuously detected
as NG for 5 trips, ECM warns the driver that engi ne control system malfunctions and MIL circuit is open by
means of operating fail-safe function.
The fail-safe function also operates when above diagnos es except MIL circuit are detected and demands the
driver to repair the malfunction.
DTC No. Detected items Engine operating condition in fail-safe mode
P0102
P0103 Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.
P0117
P0118 Engine coolant tempera-
ture sensor circuit Engine coolant temperature will be determined by ECM based on the following condition.
CONSULT-III displays the engine coolant temperature decided by ECM.
Condition Engine coolant temperature decided
(CONSULT-III display)
Just as ignition switch is turned ON
or START 40
°C (104 °F)
Approx. 4 minutes or more after
engine starting. 80
°C (176 °F)
Except as shown above 40 - 80
°C (104 - 176 °F)
(Depends on the time)
When the fail-safe system for engine coolant temperature sensor is activated, the cooling
fan operates while engine is running.
P0122
P0123
P0222
P0223
P2135 Throttle 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.
P0643 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.
P2100
P2103 Throttle 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.
P2101 Electric th rottle control
function ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P2118 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.
P2119 Electric thro ttle control ac-
tuator (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 N or P position, and engine speed will not exceed 1,000 rpm or
more.
P2122
P2123
P2127
P2128
P2138 Accelerator pedal 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.
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EC-96
< SERVICE INFORMATION >[VQ35DE]
TROUBLE DIAGNOSIS
Symptom Matrix Chart
INFOID:0000000001325930
SYSTEM — BASIC ENGINE CONTROL SYSTEM
Engine operating condition in fail-safe mode Engine speed will not rise more than 2,500 rpm due to the fuel cut
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 pump circuit 11232 22 3 2 EC-558
Fuel pressure regulator system 334444444 4EC-87
Fuel injector circuit 11232 22 2EC-552
Evaporative emission system 334444444 4EC-40
Air Positive crankcase ventilation sys-
tem 334444444 41
EC-51
Incorrect idle speed adjustment 1 1 1 1 1 EC-80
Electric throttle control actuator 112332222 2 2EC-494,
EC-504
IgnitionIncorrect ignition timing adjustment33111 11 1 EC-80
Ignition circuit 11222 22 2EC-569
Power supply and ground circuit 22333 33 23 EC-140
Mass air flow sensor circuit
1
12 2
222 2 EC-175,
EC-182
Engine coolant temperature sensor circuit
333
EC-193,
EC-204
Air fuel ratio (A/F) sensor EC-220
EC-220
EC-228
EC-236
EC-532
Throttle position sensor circuit
22EC-198
,
EC-302
,
EC-447
,
EC-449
,
EC-518
Accelerator pedal position sensor circuit 3 2 1 EC-424
,
EC-506
,
EC-512
,
EC-524
Knock sensor circuit 2 3 EC-315
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TROUBLE DIAGNOSISEC-97
< SERVICE INFORMATION > [VQ35DE]
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1 - 6: The numbers refer to the order of inspection.
(continued on next page)
SYSTEM — ENGINE MECHANICAL & OTHER
Crankshaft position sensor (POS) circuit 2 2
EC-319
Camshaft position sensor (PHASE) circuit 3 2EC-324
Vehicle speed signal circuit 2 3 3 3EC-407
Power steering pressure sensor circuit 2 3 3EC-413
ECM 22333333333EC-418,
EC-422
Intake valve timing control solenoid valve cir-
cuit 32 13223 3
EC-168
Park/neutral position (PNP) switch circuit 3 3 3 3 3 EC-429
Refrigerant pressure sensor circuit 2 3 3 4 EC-581
Electrical load signal circuit 3EC-550
Air conditioner circuit 223333333 3 2AT C - 3 2
ABS actuator and electric unit (control unit) 4BRC-13
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
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EC-98
< SERVICE INFORMATION >[VQ35DE]
TROUBLE DIAGNOSIS
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
5 FL-10
Fuel piping 5 5 5 5 5 5
EM-45
Va p o r l o c k —
Valve deposit 5 555 55 5 —
Poor fuel (Heavy weight gasoline,
Low octane) —
Air Air duct
55555 5 EM-17
Air cleaner
EM-17
Air leakage from air duct
(Mass air flow sensor — electric
throttle control actuator)
5555 EM-17
Electric throttle control actuator
EM-19
Air leakage from intake manifold/
Collector/GasketEM-19,
EM-24
Cranking Battery 111111
11
SC-4
Generator circuit
SC-19
Starter circuit 3SC-8
Signal plate 6EM-122
Park/neutral position (PNP)
switch4
AT- 1 0 2
Engine Cylinder head
55555 55 5 EM-100
Cylinder head gasket 4 3
Cylinder block
66666 66 6 4
EM-122
Piston
Piston ring
Connecting rod
Bearing
Crankshaft
Va l v e
mecha-
nism Timing chain
55555 55 5 EM-64
Camshaft
EM-83
Intake valve timing controlEM-64
Intake valve
3EM-100
Exhaust valve
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TROUBLE DIAGNOSISEC-99
< SERVICE INFORMATION > [VQ35DE]
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1 - 6: The numbers refer to the order of inspection. Exhaust Exhaust manifold/Tube/Muffler/
Gasket 55555 55 5 EM-26
,
EX-
3Three way catalyst
Lubrica-
tion Oil pan/Oil strainer/Oil pump/Oil
filter/Oil gallery/Oil cooler
55555 55 5 EM-30
,
LU-
15, LU-8,
LU-12
Oil level (Low)/Filthy oil LU-5
Cooling
Radiator/Hose/Radiator filler cap
55555 55 45 CO-13,
CO-16
Thermostat 5 CO-27
Water pumpCO-22
Water galleryCO-29
Cooling fan 5EC-210
Coolant level (Low)/Contaminat-
ed coolant5
CO-10
IVIS (Infiniti Vehicle Immobilizer System —
NATS) 11 EC-53 or
BL-185
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
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