INFINITI FX35 2006 Service Manual

DTC P0102, P0103 MAF SENSOR EC-867
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Revision: 2006 December 2006 FX35/FX45
DTC P0102, P0103 MAF SENSORPFP:22680
Component DescriptionNBS0043L
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 ModeNBS0043M
Specification data are reference values.
On Board Diagnosis LogicNBS0043N
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-801, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
CAL/LD VALUE

Engine: After warming up

Selector lever: P or N

Air conditioner switch: OFF

No load Idle 14% - 33%
2,500 rpm 12% - 25%
MASS AIRFLOW

Engine: After warming up

Selector lever: P or N

Air conditioner switch: OFF

No load Idle 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
P0102
0102 Mass air flow sensor
circuit low input An 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
0103 Mass air flow sensor
circuit high input An 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-868
[VK45DE]
DTC P0102, P0103 MAF SENSOR
Revision: 2006 December 2006 FX35/FX45
DTC Confirmation ProcedureNBS0043O
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-870, "
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-870, "
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-870, "
Diagnostic Procedure" .
With GST
Follow the procedure “With CONSULT-II” above.
SEF058Y
SEF058Y

DTC P0102, P0103 MAF SENSOR EC-869
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Revision: 2006 December 2006 FX35/FX45
Wiring DiagramNBS0043P
TBWM1327E

EC-870
[VK45DE]
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 ProcedureNBS0043Q
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 to 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 - 1.3V
[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/B Power supply for ECM
[Ignition switch: ON] BATTERY VOLTAGE
(11 - 14V)

DTC P0102, P0103 MAF SENSOR EC-871
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Revision: 2006 December 2006 FX35/FX45
3. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-818, "
Ground Inspection" .
OK or NG
OK >> GO TO 4.
NG >> Repair or replace ground connections.
4. CHECK MAF SENSOR POWER SUPPLY CIRCUIT
1. Disconnect mass air flow (MAF) sensor (1) harness connector.
2. Turn ignition switch ON.
3. Check voltage between MAF sensor terminal 2 and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors E211, M41

Harness connectors M82, F102

Harness for open or short between mass air flow sensor and ECM

Harness for open or short between mass air flow sensor and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors.
PBIB2195E
PBIB3230E
Voltage: Battery voltage
PBIB1168E

EC-872
[VK45DE]
DTC P0102, P0103 MAF SENSOR
Revision: 2006 December 2006 FX35/FX45
6. CHECK MAF SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between MAF sensor terminal 3 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 7.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
7. CHECK MAF SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between MAF sensor terminal 4 and ECM terminal 51. Refer to Wiring Diagram.
2. 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 MASS AIR FLOW SENSOR
Refer to EC-872, "
Component Inspection" .
OK or NG
OK >> GO TO 9.
NG >> Replace mass air flow sensor.
9. CHECK INTERMITTENT INCIDENT
Refer to EC-811, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>> INSPECTION END
Component InspectionNBS0043R
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. Continuity should exist.
Continuity should exist.
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 - 1.3
2,500 rpm (Engine is warmed-up to
normal operating temperature.) 1.6 - 2.0
Idle to about 4,000 rpm 1.0 - 1.3 to Approx. 2.4*
PBIB2371E

DTC P0102, P0103 MAF SENSOR EC-873
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Revision: 2006 December 2006 FX35/FX45
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
b. If NG, repair or replace malfunctioning part and perform step 2 to 3 again. If OK, go to next step.
5. Turn ignition switch OFF.
6. Disconnect mass air flow sensor harness connector and reconnect it again.
7. Perform step 2 and 3 again.
8. If NG, clean or replace mass air flow sensor.
Removal and InstallationNBS0043S
MASS AIR FLOW SENSOR
Refer to EM-177, "AIR CLEANER AND AIR DUCT" .
Condition Voltage V
Ignition switch ON (Engine stopped.) Approx. 0.4
Idle (Engine is warmed-up to normal
operating temperature.) 1.0 - 1.3
2,500 rpm (Engine is warmed-up to
normal operating temperature.) 1.6 - 2.0
Idle to about 4,000 rpm 1.0 - 1.3 to Approx. 2.4*
PBIB1106E

EC-874
[VK45DE]
DTC P0112, P0113 IAT SENSOR
Revision: 2006 December 2006 FX35/FX45
DTC P0112, P0113 IAT SENSORPFP:22630
Component DescriptionNBS0043T
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.

*: These data are reference values and are 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 LogicNBS0043U
DTC Confirmation ProcedureNBS0043V
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-877, "
Diagnostic Procedure"
.
PBIB1604E
Intake air temperature
° C ( °F) Voltage* V Resistance k
Ω
25 (77) 3.3 1.800 - 2.200
80 (176) 1.2 0.283 - 0.359
SEF012P
DTC No. Trouble diagnosis
name DTC detecting condition Possible cause
P0112
0112 Intake air tempera-
ture sensor circuit
low input An 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
0113 Intake air tempera-
ture sensor circuit
high input An excessively high voltage from the sensor is
sent to ECM.
SEF058Y

DTC P0112, P0113 IAT SENSOR EC-875
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Revision: 2006 December 2006 FX35/FX45
WITH GST
Follow the procedure “WITH CONSULT-II” above.

EC-876
[VK45DE]
DTC P0112, P0113 IAT SENSOR
Revision: 2006 December 2006 FX35/FX45
Wiring DiagramNBS0043W
TBWM0723E