2004 INFINITI FX35 air intake

DTC P0101 MAF SENSOR
EC-165
[VQ35DE]
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MA
EC
Revision: 2004 November 2004 FX35/FX45
DTC P0101 MAF SENSORPFP:22680
Component DescriptionABS006LZ
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, the electric current supplied to hot wire is changed to
maintain 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 ModeABS006M0
Specification data are reference values.
On Board Diagnosis LogicABS006M1
This self-diagnosis has the one trip detection logic.
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 name DTC detecting condition Possible cause
P0101
0101Mass air flow sensor cir-
cuit range/performance
problemA)A high voltage from the sensor is sent to ECM
under light load driving condition.

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

Mass air flow sensor
B)A low voltage from the sensor is sent to ECM
under heavy load driving condition.

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

Intake air leaks

Mass air flow sensor

DTC P0101 MAF SENSOR
EC-169
[VQ35DE]
C
D
E
F
G
H
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J
K
L
MA
EC
Revision: 2004 November 2004 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 ProcedureABS00CGP
1. INSPECTION START
Which malfunction (A or B) is duplicated?
A or B
A>>GO TO 3.
B>>GO TO 2.
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
COLORITEM CONDITION DATA (DC Voltage)
51 L/W Mass air flow sensor[Engine is running]

Warm-up condition

Idle speed0.9 - 1.2V
[Engine is running]

Warm-up condition

Engine speed is 2,500 rpm1.6 - 1.9V
67 B/WSensor ground
(Mass air flow sensor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
111 W / BECM relay
(Self shut-off)[Engine is running]
[Ignition switch: OFF]

For a few seconds after turning ignition
switch OFF0 - 1.5V
[Ignition switch: OFF]

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

DTC P0102, P0103 MAF SENSOR
EC-173
[VQ35DE]
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MA
EC
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-176
[VQ35DE]
DTC P0102, P0103 MAF SENSOR
Revision: 2004 November 2004 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 ProcedureABS00CGQ
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
COLORITEM CONDITION DATA (DC Voltage)
51 L/W Mass air flow sensor[Engine is running]

Warm-up condition

Idle speed0.9 - 1.2V
[Engine is running]

Warm-up condition

Engine speed is 2,500 rpm1.6 - 1.9V
67 B/WSensor ground
(Mass air flow sensor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
111 W / BECM relay
(Self shut-off)[Engine is running]
[Ignition switch: OFF]

For a few seconds after turning ignition
switch OFF0 - 1.5V
[Ignition switch: OFF]

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

EC-180
[VQ35DE]
DTC P0112, P0113 IAT SENSOR
Revision: 2004 November 2004 FX35/FX45
DTC P0112, P0113 IAT SENSORPFP:22630
Component DescriptionABS006MG
The intake air temperature sensor is built-into mass air flow sensor.
The sensor detects intake air temperature and transmits a signal to
the ECM.
The temperature sensing unit uses a thermistor which is sensitive to
the change in temperature. Electrical resistance of the thermistor
decreases in response to the temperature rise.

*: This data is reference value and is measured between ECM terminal 34 (Intake air
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 terminals, such as the ground.
On Board Diagnosis LogicABS006MH
DTC Confirmation ProcedureABS006MI
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.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Wait at least 5 seconds.
4. If 1st trip DTC is detected, go to EC-183, "
Diagnostic Procedure"
.
PBIB1604E
Intake air temperature
°C (°F)Voltage* V Resistance kΩ
25 (77) 3.32 1.94 - 2.06
80 (176) 1.23 0.295 - 0.349
SEF012P
DTC No.Trouble diagnosis
nameDTC detecting condition Possible cause
P0112
0112Intake air tempera-
ture 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 temperature sensor
P0113
0113Intake air tempera-
ture sensor circuit
high inputAn excessively high voltage from the sensor is
sent to ECM.
SEF058Y

DTC P0112, P0113 IAT SENSOR
EC-183
[VQ35DE]
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EC
Revision: 2004 November 2004 FX35/FX45
Diagnostic ProcedureABS00CGR
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground three screws on the body. Refer to EC-141, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2. CHECK INTAKE AIR TEMPERATURE SENSOR POWER SUPPLY CIRCUIT
1. Disconnect mass air flow sensor (intake air temperature sensor
is built-into) harness connector.
2. Turn ignition switch ON.
3. Check voltage between mass air flow sensor terminal 5 and
ground.
OK or NG
OK >> GO TO 3.
NG >> Repair harness or connectors.
3. CHECK INTAKE AIR TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between mass air flow sensor terminal 6 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.
PBIB2195E
PBIB1565E
Voltage: Approximately 5V
PBIB1169E
Continuity should exist.

EC-184
[VQ35DE]
DTC P0112, P0113 IAT SENSOR
Revision: 2004 November 2004 FX35/FX45
4. CHECK INTAKE AIR TEMPERATURE SENSOR
Refer to EC-184, "
Component Inspection" .
OK or NG
OK >> GO TO 5.
NG >> Replace mass air flow sensor (with intake air temperature sensor).
5. CHECK INTERMITTENT INCIDENT
Refer to EC-135, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionABS006ML
INTAKE AIR TEMPERATURE SENSOR
1. Check resistance between mass air flow sensor terminals 5 and
6 under the following conditions.
2. If NG, replace mass air flow sensor (with intake air temperature
sensor).
Removal and InstallationABS006MM
MASS AIR FLOW SENSOR
Refer to EM-17, "AIR CLEANER AND AIR DUCT" .
Intake air temperature °C (°F) Resistance kΩ
25 (77) 1.94 - 2.06
PBIB1604E
SEF012P

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