engine INFINITI FX35 2006 Service Manual

EC-198
[VQ35DE]
DTC P0102, P0103 MAF SENSOR
Revision: 2006 December 2006 FX35/FX45
DTC Confirmation ProcedureNBS003NF
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
PROCEDURE FOR DTC P0102
With CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Start engine and wait at least 5 seconds.
4. If DTC is detected, go to EC-200, "
Diagnostic Procedure" .
With GST
Follow the procedure “With CONSULT-II” above.
PROCEDURE FOR DTC P0103
With CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Wait at least 5 seconds.
4. If DTC is detected, go to EC-200, "
Diagnostic Procedure" .
If DTC is not detected, go to next step.
5. Start engine and wait at least 5 seconds.
6. If DTC is detected, go to EC-200, "
Diagnostic Procedure" .
With GST
Follow the procedure “With CONSULT-II” above.
SEF058Y
SEF058Y

EC-200
[VQ35DE]
DTC P0102, P0103 MAF SENSOR
Revision: 2006 December 2006 FX35/FX45
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
Diagnostic ProcedureNBS003NH
1. INSPECTION START
Which malfunction (P0102 or P0103) is duplicated?
P0102 or P0103
P0102 >> GO TO 2.
P0103 >> GO TO 3.
2. CHECK INTAKE SYSTEM
Check the following for connection.

Air duct

Va c u u m h o s e s

Intake air passage between air duct and intake manifold
OK or NG
OK >> GO TO 3.
NG >> Reconnect the parts.
TER-
MINAL NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
51 L/W Mass air flow sensor [Engine is running]

Warm-up condition

Idle speed
1.0 - 1.2V
[Engine is running]

Warm-up condition

Engine speed: 2,500 rpm 1.6 - 2.0V
67 B/W Sensor ground [Engine is running]

Warm-up condition

Idle speed Approximately 0V
111 W / B ECM relay
(Self shut-off) [Engine is running]
[Ignition switch: OFF]

For a few seconds after turning ignition
switch OFF 0 - 1.5V
[Ignition switch: OFF]

More than a few seconds after turning igni-
tion switch OFF BATTERY VOLTAGE
(11 - 14V)
11 9
120 R
R Power supply for ECM
[Ignition switch: ON] BATTERY VOLTAGE
(11 - 14V)

DTC P0102, P0103 MAF SENSOR EC-203
[VQ35DE]
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EC
Revision: 2006 December 2006 FX35/FX45
Component InspectionNBS003NI
MASS AIR FLOW SENSOR With CONSULT-II
1. Reconnect all harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.
3. Connect CONSULT-II and select “DATA MONITOR” mode.
4. Select “MAS A/F SE-B1” and check indication under the follow- ing conditions.
*: Check for linear voltage rise in response to engine being increased to about
4,000 rpm.
5. If the voltage is out of specification, proceed the following.
a. Check for the cause of uneven air flow through mass air flow sensor. Refer to following.

Crushed air ducts

Malfunctioning seal of air cleaner element

Uneven dirt of air cleaner element

Improper specification of intake air system parts
b. If NG, repair or replace malfunctioning part and perform step 2 to 4 again. If OK, go to next step.
6. Turn ignition switch OFF.
7. Disconnect mass air flow sensor harness connector and reconnect it again.
8. Perform step 2 to 4 again.
9. If NG, clean or replace mass air flow sensor.
Without CONSULT-II
1. Reconnect all harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.
3. Check voltage between ECM terminal 51 (Mass air flow sensor signal) and ground.
*: Check for linear voltage rise in response to engine being increased to about
4,000 rpm.
4. If the voltage is out of specification, proceed the following.
a. Check for the cause of uneven air flow through mass air flow sensor. Refer to following.

Crushed air ducts

Malfunctioning seal of air cleaner element

Uneven dirt of air cleaner element

Improper specification of intake air system parts
Condition MAS A/F SE-B1 (V)
Ignition switch ON (Engine stopped.) Approx. 0.4
Idle (Engine is warmed-up to normal
operating temperature.) 1.0 - 1.2
2,500 rpm (Engine is warmed-up to
normal operating temperature.) 1.6 - 2.0
Idle to about 4,000 rpm 1.0 - 1.2 to Approx. 2.4*
PBIB2371E
Condition Voltage V
Ignition switch ON (Engine stopped.) Approx. 0.4
Idle (Engine is warmed-up to normal
operating temperature.) 1.0 - 1.2
2,500 rpm (Engine is warmed-up to
normal operating temperature.) 1.6 - 2.0
Idle to about 4,000 rpm 1.0 - 1.2 to Approx. 2.4*
PBIB1106E

EC-210
[VQ35DE]
DTC P0117, P0118 ECT SENSOR
Revision: 2006 December 2006 FX35/FX45
DTC P0117, P0118 ECT SENSORPFP:22630
Component DescriptionNBS003NR
The engine coolant temperature (ECT) sensor is used to detect the
engine coolant temperature. The sensor modifies a voltage signal
from the ECM. The modified signal returns to the ECM as the engine
coolant temperature input. The sensor uses a thermistor which is
sensitive to the change in temperature. The electrical resistance of
the thermistor decreases as temperature increases.

*: This data is reference values and is measured between ECM terminal 73 (Engine
coolant temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
On Board Diagnosis LogicNBS003NS
These self-diagnoses have the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode and the MIL lights up.
SEF594K
Engine coolant temperature
° C ( °F) Voltage* V Resistance k
Ω
-10 (14) 4.4 7.0 - 11.4 20 (68) 3.5 2.1 - 2.9
50 (122) 2.2 0.68 - 1.00
90 (194) 0.9 0.236 - 0.260
SEF012P
DTC No. Trouble Diagnosis
Name DTC Detecting Condition Possible Cause
P0117
0117 Engine coolant tem-
perature sensor cir-
cuit low input An excessively low voltage from the sensor is
sent to ECM.

Harness or connectors
(Engine coolant temperature sensor circuit is
open or shorted.)

Engine coolant temperature sensor
P0118
0118 Engine coolant tem-
perature sensor cir-
cuit high input An excessively high voltage from the sensor is
sent to ECM.
Detected items Engine operating condition in fail-safe mode
Engine coolant temper- ature sensor circuit Engine 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.
Condition Engine coolant temperature decided
(CONSULT-II display)
Just as ignition switch is turned ON or START 40 °C (104 °F)
More than approx. 4 minutes after ignition ON or
START 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.

DTC P0117, P0118 ECT SENSOR EC-213
[VQ35DE]
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EC
Revision: 2006 December 2006 FX35/FX45
Diagnostic ProcedureNBS003NV
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body. Refer to EC-154, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2. CHECK ECT SENSOR POWER SUPPLY CIRCUIT
1. Disconnect engine coolant temperature (ECT) sensor harness connector.
2. Turn ignition switch ON.
3. Check voltage between ECT sensor terminal 1 and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
PBIB2625E
PBIB1563E
Voltage: Approximately 5V
PBIB0080E

EC-214
[VQ35DE]
DTC P0117, P0118 ECT SENSOR
Revision: 2006 December 2006 FX35/FX45
3. CHECK ECT SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECT sensor terminal 2 and ECM terminal 67. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
4. CHECK ENGINE COOLANT TEMPERATURE SENSOR
Refer to EC-214, "
Component Inspection" .
OK or NG
OK >> GO TO 5.
NG >> Replace engine coolant temperature sensor.
5. CHECK INTERMITTENT INCIDENT
Refer to EC-148, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>> INSPECTION END
Component InspectionNBS003NW
ENGINE COOLANT TEMPERATURE SENSOR
Check resistance between engine coolant temperature sensor termi-
nals 1 and 2 as shown in the figure.

If NG, replace engine coolant temperature sensor.
Removal and InstallationNBS003NX
ENGINE COOLANT TEMPERATURE SENSOR
Refer to CO-27, "WATER INLET AND THERMOSTAT ASSEMBLY" .
Continuity should exist.
PBIB2005E
Engine coolant temperature
°C ( °F) Resistance k Ω
20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.00
90 (194) 0.236 - 0.260
SEF012P

DTC P0122, P0123 TP SENSOR EC-215
[VQ35DE]
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D E
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G H
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EC
Revision: 2006 December 2006 FX35/FX45
DTC P0122, P0123 TP SENSORPFP:16119
Component DescriptionNBS003NY
Electric throttle control actuator consists of throttle control motor,
throttle position (TP) sensor, etc. The throttle position sensor
responds to the throttle valve movement.
The throttle position sensor has two sensors. These sensors are a
kind of potentiometers which transform the throttle valve position into
output voltage, and emit the voltage signal to the ECM. In addition,
these sensors detect the opening and closing speed of the throttle
valve and feed the voltage signals to the ECM. The ECM judges the
current opening angle of the throttle valve from these signals and the
ECM controls the throttle control motor to make the throttle valve
opening angle properly in response to driving condition.
CONSULT-II Reference Value in Data Monitor ModeNBS003NZ
Specification data are reference values.
*: Throttle position sensor 2 signal is converted by ECM internally. Thus, it differs from ECM terminal voltage signal.
On Board Diagnosis LogicNBS003O0
These self-diagnoses have the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
PBIB0145E
MONITOR ITEM CONDITION SPECIFICATION
THRTL SEN 1
THRTL SEN 2*

Ignition switch: ON
(Engine stopped)

Selector lever: D Accelerator pedal: Fully released More than 0.36V
Accelerator pedal: Fully depressed Less than 4.75V
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0122
0122 Throttle position sensor
2 circuit low input An excessively low voltage from the TP sensor
2 is sent to ECM.

Harness or connectors
(TP sensor 2 circuit is open or shorted.)
(APP sensor 2 circuit is shorted.)

Electric throttle control actuator
(TP sensor 2)

Accelerator pedal position sensor
(APP sensor 2)
P0123
0123 Throttle position sensor
2 circuit high input An excessively high voltage from the TP sen-
sor 2 is sent to ECM.
Engine operation condition in fail-safe mode
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.

EC-216
[VQ35DE]
DTC P0122, P0123 TP SENSOR
Revision: 2006 December 2006 FX35/FX45
DTC Confirmation ProcedureNBS003O1
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Start engine and let it idle for 1 second.
4. If DTC is detected, go to EC-218, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
SEF058Y

EC-218
[VQ35DE]
DTC P0122, P0123 TP SENSOR
Revision: 2006 December 2006 FX35/FX45
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
Diagnostic ProcedureNBS003O3
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body. Refer to EC-154, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TER-
MINAL NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
47 L Sensor power supply
(Throttle position sensor) [Ignition switch: ON]
Approximately 5V
50 W Throttle position sensor 1 [Ignition switch: ON]

Engine stopped

Selector lever: D

Accelerator pedal: Fully released
More than 0.36V
[Ignition switch: ON]

Engine stopped

Selector lever: D

Accelerator pedal: Fully depressed Less than 4.75V
66 B Sensor ground
(Throttle position sensor) [Engine is running]

Warm-up condition

Idle speed
Approximately 0V
69 R Throttle position sensor 2 [Ignition switch: ON]

Engine stopped

Selector lever: D

Accelerator pedal: Fully released
Less than 4.75V
[Ignition switch: ON]

Engine stopped

Selector lever: D

Accelerator pedal: Fully depressed More than 0.36V
91 G Sensor power supply
(APP sensor 2) [Ignition switch: ON]
Approximately 5V
PBIB2625E

EC-222
[VQ35DE]
DTC P0125 ECT SENSOR
Revision: 2006 December 2006 FX35/FX45
DTC P0125 ECT SENSORPFP:22630
Component DescriptionNBS003O6
NOTE:
If DTC P0125 is displayed with P0117 or P0118, first perform the trouble diagnosis for DTC P0117 or
P0118. Refer to EC-210, "
DTC P0117, P0118 ECT SENSOR" .
The engine coolant temperature (ECT) sensor is used to detect the
engine coolant temperature. The sensor modifies a voltage signal
from the ECM. The modified signal returns to the ECM as the engine
coolant temperature input. The sensor uses a thermistor which is
sensitive to the change in temperature. The electrical resistance of
the thermistor decreases as temperature increases.

*: This data is reference values and is measured between ECM terminal 73 (Engine
coolant temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output
voltage. Doing so may result in damage to the ECM's transistor. Use a ground other than ECM termi-
nals, such as the ground.
On Board Diagnosis LogicNBS003O7
SEF594K
Engine coolant
temperature °C ( °F) Voltage* V Resistance k
Ω
20 (68) 3.5 2.1 - 2.9
50 (122) 2.2 0.68 - 1.00
90 (194) 0.9 0.236 - 0.260
SEF012P
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0125
0125 Insufficient engine cool-
ant temperature for
closed loop fuel control

Voltage sent to ECM from the sensor is not
practical, even when some time has passed
after starting the engine.

Engine coolant temperature is insufficient for
closed loop fuel control.

Harness or connectors
(High resistance in the circuit)

Engine coolant temperature sensor

Thermostat