EC-98
[VQ35DE]
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
[VQ35DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
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
EC-102
[VQ35DE]
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-103
[VQ35DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2007 April2007 M35/M45
Engine Control Component Parts LocationNBS004T2
1. IPDM E/R 2. ICC brake hold relay
(ICC models only)3. Battery current sensor
4. Cooling fan relay 5. Power steering pressure sensor 6. Refrigerant pressure sensor
7. Intake valve timing control solenoid
valve (bank 1)8. Cooling fan motor-2 9. Cooling fan control module
10. Intake valve timing control solenoid
valve (bank 2)11. Cooling fan motor-1 12. Mass air flow sensor
(with built in intake air temperature
sensor)
13. Ignition coil (with power transistor)
and spark plug (bank 2)14. Camshaft position sensor (PHASE)
(Bank 2)15. Electric throttle control actuator
(with built in throttle position sensor,
throttle control motor)
16. Fuel injector (bank 2) 17. Knock sensor 18. Fuel injector (bank 1)
19. EVAP canister purge volume con-
trol solenoid valve20. Camshaft position sensor (PHASE)
(Bank 1)21. Engine coolant temperature sensor
22. Ignition coil (with power transistor)
and spark plug (bank 1)23. EVAP service port
PBIB2781E
EC-104
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
: Vehicle front
1. Mass air flow sensor
(with built in intake air temperature
sensor)2. Electric throttle control actuator
(with built in throttle position sensor,
throttle control motor)3. Cooling fan motor-1
4. Cooling fan motor-2 5. Cooling fan control module 6. Refrigerant pressure sensor har-
ness connector
7. PCV valve 8. Engine coolant temperature sensor
harness connector9. Fuel dumper
PBIB3351E
EC-120
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
69 R Throttle position sensor 2[Ignition switch: ON]
Engine stopped
Selector lever: D
Accelerator pedal: Fully releasedLess than 4.75V
[Ignition switch: ON]
Engine stopped
Selector lever: D
Accelerator pedal: Fully depressedMore than 0.36V
70 L/R Refrigerant pressure sensor[Engine is running]
Warm-up condition
Both A/C switch and blower fan motor
switch: ON (Compressor operates)1.0 - 4.0V
71 L/R Battery current sensor[Engine is running]
Battery: Fully charged*
Idle speedApproximately 2.6 - 3.5V
73 Y/BEngine coolant temperature
sensor[Engine is running]Approximately 0 - 4.8V
Output voltage varies with
engine coolant temperature.
74 WHeated oxygen sensor 2
(bank 1)[Engine is running]
Revving engine from idle to 3,000 rpm
quickly 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 - Approximately 1.0V
78 BSensor ground
(Heated oxygen sensor)[Engine is running]
Warm-up condition
Idle speedApproximately 0V
82 WSensor ground
(APP sensor 1)[Engine is running]
Warm-up condition
Idle speedApproximately 0V
83 PSensor ground
(APP sensor 2)[Engine is running]
Warm-up condition
Idle speedApproximately 0V
85 V Data link connector[Ignition switch: ON]
CONSULT-II or GST: DisconnectedApproximately 5V - Battery volt-
age (11 - 14V)
86 P CAN communication line[Ignition switch: ON]Approximately 1.1 - 2.3V
Output voltage varies with the
communication status.
90 LSensor power supply
(APP sensor 1)[Ignition switch: ON]Approximately 5V
91 BRSensor power supply
(APP sensor 2)[Ignition switch: ON]Approximately 5V
94 L CAN communication line[Ignition switch: ON]Approximately 2.6 - 3.2V
Output voltage varies with the
communication status. TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
EC-124
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
ENGINE CONTROL COMPONENT PARTS/CONTROL SYSTEMS APPLICATION
ItemDIAGNOSTIC TEST MODE
WORK
SUP-
PORTSELF-DIAGNOS-
TIC RESULTS
DATA
MONI-
TORDATA
MONI-
TOR
(SPEC)ACTIVE
TESTDTC & SRT
CONFIRMATION
DTC*1FREEZE
FRAME
DATA*2SRT
STATUSDTC
WORK
SUP-
PORT
ENGINE CONTROL COMPONENT PARTS
INPUT
Crankshaft position sensor (POS)××××
Camshaft position sensor
(PHASE)××××
Mass air flow sensor×××
Engine coolant temperature sen-
sor×××××
Air fuel ratio (A/F) sensor 1×××××
Heated oxygen sensor 2×××××
Wheel sensor××××
Accelerator pedal position sensor×××
Throttle position sensor××××
Fuel tank temperature sensor××××
EVAP control system pressure
sensor×××
Intake air temperature sensor××××
Knock sensor×
Refrigerant pressure sensor××
Closed throttle position switch
(accelerator pedal position sensor
signal)××
Air conditioner switch××
Park/neutral position (PNP) switch×××
Stop lamp switch×××
Power steering pressure sensor×××
Battery voltage××
Load signal××
Fuel level sensor×××
Battery current sensor×××
ICC steering switch×××
ASCD steering switch×××
ICC brake switch×××
ASCD brake switch×××
EC-126
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
*: This function is not necessary in the usual service procedure.
SELF-DIAG RESULTS MODE
Self Diagnostic Item
Regarding items of DTC and 1st trip DTC, refer to EC-55, "EMISSION-RELATED DIAGNOSTIC INFORMA-
TION ITEMS" .)
Freeze Frame Data and 1st Trip Freeze Frame Data
EVAP SYSTEM CLOSE CLOSE THE EVAP CANISTER VENT CONTROL VALVE IN
ORDER TO MAKE EVAP SYSTEM CLOSE UNDER THE
FOLLOWING CONDITIONS.
IGN SW ON
ENGINE NOT RUNNING
AMBIENT TEMPERATURE IS ABOVE 0°C (32°F).
NO VACUUM AND NO HIGH PRESSURE IN EVAP SYS-
TEM
FUEL TANK TEMP. IS MORE THAN 0°C (32°F).
WITHIN 10 MINUTES AFTER STARTING “EVAP SYS-
TEM CLOSE”
WHEN TRYING TO EXECUTE “EVAP SYSTEM CLOSE”
UNDER THE CONDITION EXCEPT ABOVE, CONSULT-
II WILL DISCONTINUE IT AND DISPLAY APPROPRI-
ATE INSTRUCTION.
NOTE:
WHEN STARTING ENGINE, CONSULT-II MAY DISPLAY
“BATTERY VOLTAGE IS LOW. CHARGE BATTERY”,
EVEN IN USING CHARGED BATTERY.When detecting EVAP vapor leak
point of EVAP system
VIN REGISTRATION
IN THIS MODE VIN IS REGISTERED IN ECM When registering VIN in ECM
TARGET IDLE RPM ADJ*
IDLE CONDITION When setting target idle speed
TARGET IGN TIM ADJ*
IDLE CONDITION When adjusting target ignition tim-
ing WORK ITEM CONDITION USAGE
Freeze frame data
item*Description
DIAG TROUBLE
CODE
[PXXXX]
The engine control component part/control system has a trouble code, it is displayed as PXXXX. (Refer to
EC-55, "
EMISSION-RELATED DIAGNOSTIC INFORMATION ITEMS" .)
FUEL SYS-B1
“Fuel injection system status” at the moment a malfunction is detected is displayed.
One mode in the following is displayed.
Mode2: Open loop due to detected system malfunction
Mode3: Open loop due to driving conditions (power enrichment, deceleration enleanment)
Mode4: Closed loop - using oxygen sensor(s) as feedback for fuel control
Mode5: Open loop - has not yet satisfied condition to go to closed loop FUEL SYS-B2
CAL/LD VALUE [%]
The calculated load value at the moment a malfunction is detected is displayed.
COOLANT TEMP [°C]
or [°F]
The engine coolant temperature at the moment a malfunction is detected is displayed.
L-FUEL TRM-B1 [%]
“Long-term fuel trim” at the moment a malfunction is detected is displayed.
The long-term fuel trim indicates much more gradual feedback compensation to the base fuel schedule
than short-term fuel trim. L-FUEL TRM-B2 [%]
S-FUEL TRM-B1 [%]
“Short-term fuel trim” at the moment a malfunction is detected is displayed.
The short-term fuel trim indicates dynamic or instantaneous feedback compensation to the base fuel
schedule. S-FUEL TRM-B2 [%]
ENGINE SPEED
[rpm]
The engine speed at the moment a malfunction is detected is displayed.