2004 INFINITI FX35 control

DTC P0102, P0103 MAF SENSOR
EC-173
[VQ35DE]
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Revision: 2004 November 2004 FX35/FX45
DTC P0102, P0103 MAF SENSORPFP:22680
Component DescriptionABS006M8
The mass air flow sensor is placed in the stream of intake air. It mea-
sures the intake flow rate by measuring a part of the entire intake
flow. The mass air flow sensor controls the temperature of the hot
wire to a certain amount. The heat generated by the hot wire is
reduced as the intake air flows around it. The more air, the greater
the heat loss.
Therefore, electric current is supplied to hot wire is changed to main-
tain the temperature of the hot wire as air flow increases. The ECM
detects the air flow by means of this current change.
CONSULT-II Reference Value in Data Monitor ModeABS006M9
Specification data are reference values.
On Board Diagnosis LogicABS006MA
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.
PBIB1604E
MONITOR ITEM CONDITION SPECIFICATION
MAS A/F SE-B1 See EC-131, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
CAL/LD VALUE

Engine: After warming up

Shift lever: P or N

Air conditioner switch: OFF

No-loadIdle 5% - 35%
2,500 rpm 5% - 35%
MASS AIRFLOW

Engine: After warming up

Shift lever: P or N

Air conditioner switch: OFF

No-loadIdle 2.0 - 6.0 g·m/s
2,500 rpm 7.0 - 20.0 g·m/s
DTC No.Trouble diagnosis
nameDTC detecting condition Possible cause
P0102
0102Mass air flow sensor
circuit low inputAn excessively low voltage from the sensor is
sent to ECM.

Harness or connectors
(The sensor circuit is open or shorted.)

Intake air leaks

Mass air flow sensor
P0103
0103Mass air flow sensor
circuit high inputAn excessively high voltage from the sensor is
sent to ECM.

Harness or connectors
(The sensor circuit is open or shorted.)

Mass air flow sensor
Detected items Engine operating condition in fail-safe mode
Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.

EC-190
[VQ35DE]
DTC P0122, P0123 TP SENSOR
Revision: 2004 November 2004 FX35/FX45
DTC P0122, P0123 TP SENSORPFP:16119
Component DescriptionABS00CGT
Electric throttle control actuator consists of throttle control motor,
throttle position sensor, etc. The throttle position sensor responds to
the throttle valve movement.
The throttle position sensor has the 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 addi-
tion, 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 sig-
nals and the ECM controls the throttle control motor to make the
throttle valve opening angle properly in response to driving condi-
tion.
CONSULT-II Reference Value in Data Monitor ModeABS00CGU
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 LogicABS00CGV
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 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
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0122
0122Throttle position sensor
2 circuit low inputAn excessively low voltage from the TP sensor
2 is sent to ECM.

Harness or connectors
(The 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 P0123
0123Throttle position sensor
2 circuit high inputAn 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-194
[VQ35DE]
DTC P0122, P0123 TP SENSOR
Revision: 2004 November 2004 FX35/FX45
2. CHECK THROTTLE POSITION SENSOR 2 POWER SUPPLY CIRCUIT-I
1. Disconnect electric throttle control actuator harness connector.
2. Turn ignition switch ON.
3. Check voltage between electric throttle control actuator terminal
1 and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 7.
NG >> GO TO 3.
3. CHECK THROTTLE POSITION SENSOR 2 POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between electric throttle control actuator terminal 1 and ECM terminal 47.
Refer to Wiring Diagram.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace open circuit.
4. CHECK THROTTLE POSITION SENSOR 2 POWER SUPPLY CIRCUIT-III
Check the following.

Harness for short to power and short to ground, between the following terminals.
OK or NG
OK >> GO TO 5.
NG >> Repair short to ground or short to power in harness or connectors.
5. CHECK APP SENSOR
Refer to EC-568, "
Component Inspection" .
OK or NG
OK >> GO TO 11.
NG >> GO TO 6.
PBIB1557E
Voltage: Approximately 5V
PBIB0082E
Continuity should exist.
ECM terminal Sensor terminal Reference Wiring Diagram
47 Electric throttle control actuator terminal 1EC-192
91 APP sensor terminal 2EC-564

DTC P0122, P0123 TP SENSOR
EC-195
[VQ35DE]
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Revision: 2004 November 2004 FX35/FX45
6. REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace accelerator pedal assembly.
2. Perform EC-49, "
Accelerator Pedal Released Position Learning" .
3. Perform EC-49, "
Throttle Valve Closed Position Learning" .
4. Perform EC-49, "
Idle Air Volume Learning" .
>>INSPECTION END
7. CHECK THROTTLE POSITION SENSOR 2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between electric throttle control actuator terminal 5 and ECM terminal 66.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
8. CHECK THROTTLE POSITION SENSOR 2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 69 and electric throttle control actuator terminal 2.
Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
9. CHECK THROTTLE POSITION SENSOR
Refer to EC-196, "
Component Inspection" .
OK or NG
OK >> GO TO 11.
NG >> GO TO 10.
10. REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR
1. Replace the electric throttle control actuator.
2. Perform EC-49, "
Throttle Valve Closed Position Learning" .
3. Perform EC-49, "
Idle Air Volume Learning" .
>>INSPECTION END
11 . CHECK INTERMITTENT INCIDENT
Refer to EC-135, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END Continuity should exist.
Continuity should exist.

EC-196
[VQ35DE]
DTC P0122, P0123 TP SENSOR
Revision: 2004 November 2004 FX35/FX45
Component InspectionABS00CGZ
THROTTLE POSITION SENSOR
1. Reconnect all harness connectors disconnected.
2. Perform EC-49, "
Throttle Valve Closed Position Learning" .
3. Turn ignition switch ON.
4. Set selector lever to D position.
5. Check voltage between ECM terminals 50 (TP sensor 1signal),
69 (TP sensor 2signal) and ground under the following condi-
tions.
6. If NG, replace electric throttle control actuator and go to the next
step.
7. Perform EC-49, "
Throttle Valve Closed Position Learning" .
8. Perform EC-49, "
Idle Air Volume Learning" .
Removal and InstallationABS00CH0
ELECTRIC THROTTLE CONTROL ACTUATOR
Refer to EM-19, "INTAKE MANIFOLD COLLECTOR" .
Terminal Accelerator pedal Voltage
50
(Throttle position sensor 1)Fully released More than 0.36V
Fully depressed Less than 4.75V
69
(Throttle position sensor 2)Fully released Less than 4.75V
Fully depressed More than 0.36V
PBIB1608E

DTC P0125 ECT SENSOR
EC-197
[VQ35DE]
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Revision: 2004 November 2004 FX35/FX45
DTC P0125 ECT SENSORPFP:22630
Component DescriptionABS006NA
NOTE:
If DTC P0125 is displayed with P0117 or P0118, first perform the trouble diagnosis for DTC P0117 or
P0118. Refer to EC-185
.
The engine coolant temperature 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 ther-
mistor decreases as temperature increases.

*: This data is reference value 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 LogicABS006NB
This self-diagnosis has the one trip detection logic.
SEF594K
Engine coolant
temperature°C (°F)Voltage* V Resistance kΩ
-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
P0125
0125Insufficient 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

EC-214
[VQ35DE]
DTC P0133, P0153 HO2S1
Revision: 2004 November 2004 FX35/FX45
DTC P0133, P0153 HO2S1PFP:22690
Component DescriptionABS006NZ
The heated oxygen sensor 1 is placed into the exhaust manifold. It
detects the amount of oxygen in the exhaust gas compared to the
outside air. The heated oxygen sensor 1 has a closed-end tube
made of ceramic zirconia. The zirconia generates voltage from
approximately 1V in richer conditions to 0V in leaner conditions. The
heated oxygen sensor 1 signal is sent to the ECM. The ECM adjusts
the injection pulse duration to achieve the ideal air-fuel ratio. The
ideal air-fuel ratio occurs near the radical change from 1 to 0V.
CONSULT-II Reference Value in Data Monitor ModeABS006O0
Specification data are reference values.
On Board Diagnosis LogicABS006O1
To judge the malfunction of heated oxygen sensor 1, this diagnosis
measures response time of heated oxygen sensor 1 signal. The time
is compensated by engine operating (speed and load), fuel feedback
control constant, and heated oxygen sensor 1 temperature index.
Judgment is based on whether the compensated time (heated oxy-
gen sensor 1 cycling time index) is inordinately long or not.
SEF463R
SEF288D
MONITOR ITEM CONDITION SPECIFICATION
HO2S1 (B1)
HO2S1 (B2)

Engine: After warming up Maintaining engine speed at 2,000 rpm0 - 0.3V ←→ Approx. 0.6 - 1.0V
HO2S1 MNTR (B1)
HO2S1 MNTR (B2)LEAN ←→ RICH
Changes more than 5 times during
10 seconds.
SEF010V

EC-222
[VQ35DE]
DTC P0133, P0153 HO2S1
Revision: 2004 November 2004 FX35/FX45
5. CLEAR THE SELF-LEARNING DATA
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT-II.
3. Clear the self-learning control coefficient by touching “CLEAR”.
4. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected?
Is it difficult to start engine?
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.
3. Disconnect mass air flow sensor harness connector, and restart
and run engine for at least 5 seconds at idle speed.
4. Stop engine and reconnect mass air flow sensor harness con-
nector.
5. Make sure DTC P0102 is displayed.
6. Erase the DTC memory. Refer to EC-67, "
HOW TO ERASE
EMISSION-RELATED DIAGNOSTIC INFORMATION" .
7. Make sure DTC P0000 is displayed.
8. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected?
Is it difficult to start engine?
Ye s o r N o
Yes >> Perform trouble diagnosis for DTC P0171 or DTC P0172 (Refer to EC-256 or EC-265 ).
No >> GO TO 6.
SEF968Y
PBIB1565E