TROUBLE DIAGNOSIS
EC-93
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Revision: 2007 April2007 M35/M45
5. PERFORM DTC CONFIRMATION PROCEDURE
Perform DTC Confirmation Procedure for the displayed DTC*
1 , and then make sure that DTC*1 is detected
again.
At this time, always connect CONSULT-II to the vehicle, and check diagnostic results in real time on “DATA
MONITOR (AUTO TRIG)”.
If two or more DTCs*
1 are detected, refer to EC-96, "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 Confirmation 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 Confirma-
tion Procedure.
Is DTC*
1 detected?
Ye s > > G O T O 1 0 .
No >> Check according to EC-153, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
6. PERFORM BASIC INSPECTION
Perform EC-78, "
Basic Inspection" .
With CONSULT-II>>GO TO 7.
Without CONSULT-II>>GO TO 9.
7. PERFORM DATA MONITOR (SPEC) MODE
With CONSULT-II
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 CON-
SULT-II “DATA MONITOR (SPEC)” mode. Refer to EC-144, "
Diag-
nostic Procedure" .
Are they within the SP value?
Ye s > > G O T O 9 .
No >> GO TO 8.
8. DETECT MALFUNCTIONING PART BY TROUBLE DIAGNOSIS - SPECIFICATION VALUE
Detect malfunctioning part according to EC-143, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
Is malfunctioning part detected?
Ye s > > G O T O 11 .
No >> GO TO 9.
9. DETECT MALFUNCTIONING SYSTEM BY SYMPTOM MATRIX CHART
Detect malfunctioning system according to EC-99, "
Symptom Matrix Chart" based on the confirmed symptom
in step 4, and determine the trouble diagnosis order based on possible causes and symptom.
>> GO TO 10.
SEF601Z
EC-94
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TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
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-
28, "How to Perform Efficient Diagnosis for an Electrical Incident" .
Is malfunctioning part detected?
Yes >> GO TO 11.
No >> Monitor input data from related sensors or check voltage of related ECM terminals using CON-
SULT-II. Refer to EC-138, "
CONSULT-II Reference Value in Data Monitor" , EC-114, "ECM Termi-
nals and 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-68, "
HOW TO ERASE EMISSION-RELATED DIAG-
NOSTIC INFORMATION" .
>> GO TO 12.
12. FINAL CHECK
When DTC was detected in step 2, perform DTC Confirmation Procedure or Overall Function Check again,
and then make sure that the malfunction have been repaired securely.
When symptom was described from the customer, refer to confirmed symptom in step 3 or 4, and make sure
that the symptom is not detected.
OK or NG
NG (DTC*1 is detected)>>GO TO 10.
NG (Symptom remains)>>GO TO 6.
OK >> 1. Before returning the vehicle to the customer, make sure to erase unnecessary DTC*
1 in ECM
and TCM (Transmission Control Module). (Refer to EC-68, "
HOW TO ERASE EMISSION-
RELATED DIAGNOSTIC INFORMATION" and AT- 4 1 , "HOW TO ERASE DTC" .)
2. If the completion of SRT is needed, drive vehicle under the specific driving pattern. Refer to EC-
65, "Driving Pattern" .
3.INSPECTION END
*1: Include 1st trip DTC.
*2: Include 1st trip freeze frame data.
DIAGNOSTIC WORKSHEET
Description
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 MIL 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.
SEF907L
TROUBLE DIAGNOSIS
EC-97
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Revision: 2007 April2007 M35/M45
*: With ICC models2
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 P0725 P0740 P0744 P0745 P1705 P1715 P1730 P1752 P1754 P1757 P1759 P1762 P1764
P1767 P1769 P1772 P1774 A/T related sensors, solenoid valves and switches
P1217 Engine over temperature (OVERHEAT)
P1220 Fuel pump control module
P1805 Brake switch
P2100 P2103 Throttle control motor relay
P2101 Electric throttle control function
P2118 Throttle control motor
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 P0456 EVAP control system (SMALL LEAK, VERY SMALL LEAK)
P0455 EVAP control system (GROSS 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 value*
P1572 ICC brake switch/ASCD brake switch
P1574 ICC vehicle speed sensor/ASCD vehicle speed sensor
P2119 Electric throttle control actuator Priority Detected items (DTC)
EC-98
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TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
Fail-Safe ChartNBS004T0
When the DTC listed below is detected, the ECM enters fail-safe mode and the MIL lights up.
When there is an open circuit on MIL circuit, the ECM cannot warn the driver by lighting up MIL 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 MIL circuit is open by
means of operating fail-safe function.
The fail-safe function also operates when above diagnoses 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
P0103Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.
P0117
P0118Engine coolant tempera-
ture sensor circuitEngine coolant temperature will be determined by ECM based on the time after turning
ignition switch ON or START.
CONSULT-II displays the engine coolant temperature decided by ECM.
ConditionEngine coolant temperature decided
(CONSULT-II display)
Just as ignition switch is turned
ON or START40°C (104°F)
More than approx. 4 minutes after
ignition ON or START80°C (176°F)
Except as shown above40 - 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
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.
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
P2103Throttle 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 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.
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 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 N or P position, and engine speed will not exceed 1,000 rpm or
more.
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
TROUBLE DIAGNOSIS
EC-99
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Revision: 2007 April2007 M35/M45
Symptom Matrix ChartNBS004T1
SYSTEM — BASIC ENGINE CONTROL SYSTEM
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 2EC-675
Fuel pressure regulator system334444444 4EC-88
Fuel injector circuit 11232 22 2EC-669
Evaporative emission system334444444 4EC-39
Air Positive crankcase ventilation sys-
tem
334444444 41EC-51
Incorrect idle speed adjustment 1 1 1 1 1EC-78
Electric throttle control actuator 112332222 2 2EC-
604,EC-
598 ,EC-
610 ,EC-
615
IgnitionIncorrect ignition timing adjustment33111 11 1EC-78
Ignition circuit 11222 22 2EC-691
Main power supply and ground circuit22333 33 23EC-154
Mass air flow sensor circuit
1
122
222 2EC-193,
EC-202
Engine coolant temperature sensor circuit
333EC-214,
EC-226
Air fuel ratio (A/F) sensor 1 circuitEC-234
,
EC-244
,
EC-253
,
EC-262
,
EC-646
Throttle position sensor circuit
22EC-219
,
EC-342
,
EC-518
,
EC-520
,
EC-631
Accelerator pedal position sensor circuit 3 2 1EC-
617,EC-
624 ,EC-
638 ,EC-
486
Knock sensor circuit 2 3EC-359
Crankshaft position sensor (POS) circuit 2 2EC-364
TROUBLE DIAGNOSIS
EC-101
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Revision: 2007 April2007 M35/M45
SYSTEM — ENGINE MECHANICAL & OTHER
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-10
Fuel piping 5 5 5 5 5 5EM-47
Vapor lock—
Valve deposit
5 555 55 5—
Poor fuel (Heavy weight gaso-
line, Low octane)—
Air Air duct
55555 5EM-19
Air cleanerEM-19
Air leakage from air duct
(Mass air flow sensor — electric
throttle control actuator)
5555EM-19
Electric throttle control actuatorEM-21
Air leakage from intake manifold/
Collector/GasketEM-26
Cranking Battery
111111
11SC-4
Generator circuitSC-20
Starter circuit 3SC-8
Signal plate 6EM-124
PNP switch 4AT- 11 3
Engine Cylinder head
55555 55 5EM-102
Cylinder head gasket 4 3
Cylinder block
66666 66 64
EM-124
Piston
Piston ring
Connecting rod
Bearing
Crankshaft
Va l v e
mecha-
nismTiming chain
55555 55 5EM-66
CamshaftEM-85
Intake valve timing controlEM-66
Intake valve
3EM-85
Exhaust valve
EC-102
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TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
1 - 6: The numbers refer to the order of inspection.Exhaust Exhaust manifold/Tube/Muffler/
Gasket
55555 55 5EM-28
, EX-
3Three way catalyst
Lubrica-
tionOil pan/Oil strainer/Oil pump/Oil
filter/Oil gallery/Oil cooler
55555 55 5EM-31
, LU-
19 , LU-11 ,
LU-15
Oil level (Low)/Filthy oilLU-7
Cooling
Radiator/Hose/Radiator filler cap
55555 55 45CO-14,
CO-18
Thermostat 5CO-29
Water pumpCO-24
Water galleryCO-31
Cooling fan
5CO-22
Coolant level (Low)/Contami-
nated coolantCO-11
IVIS (INFINITI Vehicle Immobilizer System —
NATS)11EC-53 or
BL-244
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
TROUBLE DIAGNOSIS
EC-117
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Revision: 2007 April2007 M35/M45
21
22
23
40
41
42W
R/Y
R/B
V/R
P/L
R/WFuel injector No. 5
Fuel injector No. 3
Fuel injector No. 1
Fuel injector No. 6
Fuel injector No. 4
Fuel injector No. 2[Engine is running]
Warm-up condition
Idle speed
NOTE:
The pulse cycle changes depending on rpm
at idleBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
Warm-up condition
Engine speed: 2,000 rpmBATTERY VOLTAGE
(11 - 14V)
24 OA/F sensor 1 heater
(bank 2)[Engine is running]
Warm-up condition
Idle speedApproximately 5V
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)
32 R/GEVAP control system pres-
sure sensor[Ignition switch: ON]Approximately 1.8 - 4.8V TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
PBIB0042E
PBIB0043E
PBIB1584E