ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-75
[VQ35DE]
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Revision: 2004 November 2004 FX35/FX45
RELATIONSHIP BETWEEN MIL, DTC, 1ST TRIP DTC AND DRIVING PATTERNS EXCEPT FOR
“MISFIRE
*1: When the same malfunction is
detected in two consecutive trips,
MIL will light up.*2: MIL will go off after vehicle is driven
3 times (pattern B) without any mal-
functions.*3: When the same malfunction is
detected in two consecutive trips, the
DTC and the freeze frame data will
be stored in ECM.
*4: The DTC and the freeze frame data
will not be displayed any longer after
vehicle is driven 40 times (pattern A)
without the same malfunction.
(The DTC and the freeze frame data
still remain in ECM.)*5: When a malfunction is detected for
the first time, the 1st trip DTC and
the 1st trip freeze frame data will be
stored in ECM.*6: 1st trip DTC will be cleared after
vehicle is driven once (pattern B)
without the same malfunction.
*7: When the same malfunction is
detected in the 2nd trip, the 1st trip
freeze frame data will be cleared.
SEF393SD
EC-82
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
Fail-Safe ChartABS006KQ
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 MIL up 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.
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 N or P 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.
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
EC-86
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
10. CHECK IGNITION TIMING
1. Run engine at idle.
2. Check ignition timing with a timing light.
OK or NG
OK >>INSPECTION END
NG >> GO TO 11.
11 . PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING
1. Stop engine.
2. Perform EC-49, "
Accelerator Pedal Released Position Learning" .
>> GO TO 12.
12. PERFORM THROTTLE VALVE CLOSED POSITION LEARNING
Perform EC-49, "
Throttle Valve Closed Position Learning" .
>> GO TO 13.
13. PERFORM IDLE AIR VOLUME LEARNING
Refer to EC-49, "
Idle Air Volume Learning" .
Is Idle Air Volume Learning carried out successfully?
Ye s o r N o
Yes >> GO TO 14.
No >> 1. Follow the instruction of Idle Air Volume Learning.
2. GO TO 4.
14. CHECK TARGET IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Read idle speed in “DATA MONITOR” mode with CONSULT-II.
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed.
OK or NG
OK >> GO TO 15.
NG >> GO TO 17.15 ± 5° BTDC (in P or N position)
PBIB1602E
650 ± 50 rpm (in P or N position)
650 ± 50 rpm (in P or N position)
SEF174Y
TROUBLE DIAGNOSIS
EC-87
[VQ35DE]
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Revision: 2004 November 2004 FX35/FX45
15. CHECK IGNITION TIMING AGAIN
1. Run engine at idle.
2. Check ignition timing with a timing light.
OK or NG
OK >>INSPECTION END
NG >> GO TO 16.
16. CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM-63, "
TIMING CHAIN" .
OK or NG
OK >> GO TO 17.
NG >> 1. Repair the timing chain installation.
2. GO TO 4.
17. DETECT MALFUNCTIONING PART
Check the following.
Check camshaft position sensor (PHASE) and circuit. Refer to EC-308 .
Check crankshaft position sensor (POS) and circuit. Refer to EC-302 .
OK or NG
OK >> GO TO 18.
NG >> 1. Repair or replace.
2. GO TO 4.
18. CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function. (ECM may be the cause of an incident, but
this is a rare case.)
2. Perform initialization of IVIS (NATS) system and registration of IVIS (NATS) ignition key IDs. Refer to EC-
68, "IVIS (Infiniti Vehicle Immobilizer System — NATS)" .
>> GO TO 4. 15 ± 5° BTDC (in P or N position)
PBIB1602E
EC-108
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
99 G/YICC steering switch
(models with ICC system)[Ignition switch: ON]
ICC steering switch: OFFApproximately 4.3V
[Ignition switch: ON]
ON/OFF(MAIN) switch: PressedApproximately 0V
[Ignition switch: ON]
CANCEL switch: PressedApproximately 1.3V
[Ignition switch: ON]
DISTANCE switch: PressedApproximately 2.2V
[Ignition switch: ON]
COAST/SET switch: PressedApproximately 3.0V
[Ignition switch: ON]
ACCEL/RESUME switch: PressedApproximately 3.7V
99 G/YASCD steering switch
(models with ASCD system)[Ignition switch: ON]
ASCD steering switch: OFFApproximately 4.0V
[Ignition switch: ON]
ON/OFF(MAIN) switch: PressedApproximately 0V
[Ignition switch: ON]
CANCEL switch: PressedApproximately 1.0V
[Ignition switch: ON]
COAST/SET switch: PressedApproximately 2.0V
[Ignition switch: ON]
ACCEL/RESUME switch: PressedApproximately 3.0V
101 P/L Stop lamp switch[Ignition switch: OFF]
Brake pedal: Fully releasedApproximately 0V
[Ignition switch: OFF]
Brake pedal: Slightly depressedBATTERY VOLTAGE
(11 - 14V)
102 LG/B PNP switch[Ignition switch: ON]
Shift lever: P or NApproximately 0V
[Ignition switch: ON]
Except above positionBATTERY VOLTAGE
(11 - 14V)
104 L/OR Throttle control motor relay[Ignition switch: OFF]BATTERY VOLTAGE
(11 - 14V)
[Ignition switch: ON]0 - 1.0V
106 R/BAccelerator pedal position
sensor 1[Ignition switch: ON]
Engine stopped
Accelerator pedal: Fully released0.5 - 1.0V
[Ignition switch: ON]
Engine stopped
Accelerator pedal: Fully depressed3.9 - 4.7V
107 PU/WFuel tank temperature sen-
sor[Engine is running]Approximately 0 - 4.8V
Output voltage varies with fuel
tank temperature.
108 SBICC brake switch
(models with ICC system)
ASCD brake switch
(models with ASCD system)[Ignition switch: ON]
Brake pedal: DepressedApproximately 0V
[Ignition switch: ON]
Brake pedal: Fully releasedBATTERY VOLTAGE
(11 - 14V) TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
TROUBLE DIAGNOSIS
EC-115
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Revision: 2004 November 2004 FX35/FX45FUEL T/TEMP SE
[°C] or [°F]×The fuel temperature (determined by the
signal voltage of the fuel tank temperature
sensor) is displayed.
INT/A TEMP SE
[°C] or [°F]××
The intake air temperature (determined by
the signal voltage of the intake air tempera-
ture sensor) is indicated.
EVAP SYS PRES [V]×
The signal voltage of EVAP control system
pressure sensor is displayed.
FUEL LEVEL SE [V]×
The signal voltage of the fuel level sensor is
displayed.
START SIGNAL
[ON/OFF]××
Indicates start signal status [ON/OFF] com-
puted by the ECM according to the signals
of engine speed and battery voltage.After starting the engine, [OFF] is dis-
played regardless of the starter sig-
nal.
CLSD THL POS
[ON/OFF]××
Indicates idle position [ON/OFF] computed
by ECM according to the accelerator pedal
position sensor signal.
AIR COND SIG
[ON/OFF]××
Indicates [ON/OFF] condition of the air con-
ditioner switch as determined by the air
conditioner signal.
P/N POSI SW
[ON/OFF]××
Indicates [ON/OFF] condition from the park/
neutral position (PNP) switch signal.
PW/ST SIGNAL
[ON/OFF]××
[ON/OFF] condition of the power steering
system (determined by the signal voltage of
the power steering pressure sensor signal)
is indicated.
LOAD SIGNAL
[ON/OFF]××
Indicates [ON/OFF] condition from the elec-
trical load signal.
ON: Rear window defogger switch is ON
and/or lighting switch is in 2nd position.
OFF: Both rear window defogger switch
and lighting switch are OFF.
SNOW MODE SW
[ON/OFF]
Indicates [ON/OFF] condition from the
snow mode switch signal.
IGNITION SW
[ON/OFF]×
Indicates [ON/OFF] condition from ignition
switch signal.
HEATER FAN SW
[ON/OFF]×
Indicates [ON/OFF] condition from the
heater fan switch signal.
BRAKE SW
[ON/OFF]
Indicates [ON/OFF] condition from the stop
lamp switch signal.
INJ PULSE-B1
[msec]×
Indicates the actual fuel injection pulse
width compensated by ECM according to
the input signals.When the engine is stopped, a cer-
tain computed value is indicated.
INJ PULSE-B2
[msec]
IGN TIMING [BTDC]×
Indicates the ignition timing computed by
ECM according to the input signals.When the engine is stopped, a cer-
tain value is indicated.
CAL/LD VALUE [%]
Calculated load value indicates the value of
the current air flow divided by peak air flow.
MASS AIRFLOW
[g·m/s]
Indicates the mass air flow computed by
ECM according to the signal voltage of the
mass air flow sensor. Monitored item [Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSDescription Remarks
EC-118
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
DATA MONITOR (SPEC) MODE
Monitored Item
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
ACTIVE TEST MODE
Test Item
Voltage [V]
Voltage, frequency, duty cycle or pulse
width measured by the probe.
Only # is displayed if item is unable
to be measured.
Figures with #s are temporary ones.
They are the same figures as an
actual piece of data which was just
previously measured. Frequency [msec],
[Hz] or [%]
DUTY-HI
DUTY-LOW
PLS WIDTH-HI
PLS WIDTH-LOWMonitored item [Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSDescription Remarks
Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
ENG SPEED [rpm]××
Indicates the engine speed computed
from the signal of the crankshaft position
sensor (POS) and camshaft position
sensor (PHASE).
MAS A/F SE-B1 [V]××
The signal voltage of the mass air flow
sensor specification is displayed.When engine is running specification
range is indicated.
B/FUEL SCHDL
[msec]×
Base fuel schedule indicates the fuel
injection pulse width programmed into
ECM, prior to any learned on board cor-
rection.
When engine is running specification
range is indicated.
A/F ALPHA-B1 [%]
A/F ALPHA-B2 [%]×
The mean value of the air-fuel ratio feed-
back correction factor per cycle is indi-
cated.When engine is running specification
range is indicated.
This data also includes the data for the
air-fuel ratio learning control.
TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
FUEL INJEC-
TION
Engine: Return to the original
trouble condition
Change the amount of fuel injec-
tion using CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.
Harness and connectors
Fuel injector
Heated oxygen sensor 1
IGNITION TIM-
ING
Engine: Return to the original
trouble condition
Timing light: Set
Retard the ignition timing using
CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.
Perform Idle Air Volume Learning.
POWER BAL-
ANCE
Engine: After warming up, idle
the engine.
A/C switch: OFF
Shift lever: P or N
Cut off each injector signal one at
a time using CONSULT-II.Engine runs rough or dies.
Harness and connectors
Compression
Fuel injector
Power transistor
Spark plug
Ignition coil
TROUBLE DIAGNOSIS
EC-125
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Revision: 2004 November 2004 FX35/FX45
CONSULT-II Reference Value in Data MonitorABS006KZ
Remarks:
Specification data are reference values.
Specification data are output/input values which are detected or supplied by the ECM at the connector.
* Specification data may not be directly related to their components signals/values/operations.
i.e. Adjust ignition timing with a timing light before monitoring IGN TIMING, because the monitor may show the specification data in
spite of the ignition timing not being adjusted to the specification data. This IGN TIMING monitors the data calculated by the ECM
according to the signals input from the camshaft position sensor and other ignition timing related sensors.
MONITOR ITEM CONDITION SPECIFICATION
ENG SPEED
Run engine and compare CONSULT-II value with the tachometer indica-
tion.Almost the same speed as the
tachometer indication.
MAS A/F SE-B1 See EC-131, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
B/FUEL SCHDL See EC-131, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
A/F ALPHA-B1
A/F ALPHA-B2See EC-131, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
COOLAN TEMP/S
Engine: After warming up More than 70°C (158°F)
HO2S1 (B1)
HO2S1 (B2)
Engine: After warming upMaintaining engine speed at 2,000
rpm0 - 0.3V ←→ Approx. 0.6 -
1.0V
HO2S2 (B1)
HO2S2 (B2)
Warm-up condition
After keeping engine speed
between 3,500 and 4,000 rpm for
1 minute and at idle for 1 minute
under no load.Revving engine from idle to 3,000 rpm
quickly0 - 0.3V ←→ Approx. 0.6 -
1.0V
HO2S1 MNTR (B1)
HO2S1 MNTR (B2)
Engine: After warming upMaintaining engine speed at 2,000
rpmLEAN ←→ RICH
Changes more than 5 times
during 10 seconds.
HO2S2 MNTR (B1)
HO2S2 MNTR (B2)
Warm-up condition
After keeping engine speed
between 3,500 and 4,000 rpm for
1 minute and at idle for 1 minute
under no load.Revving engine from idle to 3,000 rpm
quicklyLEAN ←→ RICH
VEH SPEED SE
Turn drive wheels and compare CONSULT-II value with the speedometer
indication.Almost the same speed as the
speedometer indication
BATTERY VOLT
Ignition switch: ON (Engine stopped) 11 - 14V
ACCEL SEN1
Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.5 - 1.0V
Accelerator pedal: Fully depressed 4.0 - 4.8V
ACCEL SEN2*
Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.3 - 1.2V
Accelerator pedal: Fully depressed 3.9 - 4.8V
THRTL SEN1
THRTL SEN2*
Ignition switch: ON
(Engine stopped)
Shift lever: DAccelerator pedal: Fully released More than 0.36V
Accelerator pedal: Fully depressed Less than 4.75V
EVAP SYS PRES
Ignition switch: ON Approx. 1.8 - 4.8V
START SIGNAL
Ignition switch: ON → START → ON OFF → ON → OFF
CLSD THL POS
Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released ON
Accelerator pedal: Slightly depressed OFF
AIR COND SIG
Engine: After warming up, idle
the engineAir conditioner switch: OFF OFF
Air conditioner switch: ON
(Compressor operates.)ON
P/N POSI SW
Ignition switch: ONShift lever: P or N ON
Shift lever: Except above OFF
PW/ST SIGNAL
Engine: After warming up, idle
the engineSteering wheel is in neutral position
(Forward direction)OFF
Steering wheel is turned. ON