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![INFINITI FX35 2004 Service Manual EC-820
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DTC P0037, P0038, P0057, P0058 HO2S2 HEATER
Revision: 2004 November 2004 FX35/FX45
2. CHECK HO2S2 POWER SUPPLY CIRCUIT
1. Disconnect heated oxygen sensor 2 harness connector.
2. Turn i INFINITI FX35 2004 Service Manual EC-820
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DTC P0037, P0038, P0057, P0058 HO2S2 HEATER
Revision: 2004 November 2004 FX35/FX45
2. CHECK HO2S2 POWER SUPPLY CIRCUIT
1. Disconnect heated oxygen sensor 2 harness connector.
2. Turn i](/manual-img/42/57021/w960_57021-2160.png)
EC-820
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DTC P0037, P0038, P0057, P0058 HO2S2 HEATER
Revision: 2004 November 2004 FX35/FX45
2. CHECK HO2S2 POWER SUPPLY CIRCUIT
1. Disconnect heated oxygen sensor 2 harness connector.
2. Turn ignition switch ON.
3. Check voltage between HO2S2 terminal 2 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3. DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E19, E49
IPDM E/R connector E7
10A fuse
Harness for open or short between heated oxygen sensor 2 and fuse
>> Repair open circuit or short to ground or short to power in harness or connectors.
4. CHECK HO2S2 OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal and HO2S2 terminal as follows.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
PBIB1534E
Voltage: Battery voltage
PBIB0969E
DTCTerminals
Bank
ECM Sensor
P0037, P0038 6 3 1
P0057, P0058 25 3 2
Continuity should exist.
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![INFINITI FX35 2004 Service Manual DTC P0037, P0038, P0057, P0058 HO2S2 HEATER
EC-821
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5. CHECK HEATED OXYGEN SENSOR 2 HEATER
Refer to EC-821, "
Component Inspect INFINITI FX35 2004 Service Manual DTC P0037, P0038, P0057, P0058 HO2S2 HEATER
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5. CHECK HEATED OXYGEN SENSOR 2 HEATER
Refer to EC-821, "
Component Inspect](/manual-img/42/57021/w960_57021-2161.png)
DTC P0037, P0038, P0057, P0058 HO2S2 HEATER
EC-821
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5. CHECK HEATED OXYGEN SENSOR 2 HEATER
Refer to EC-821, "
Component Inspection" .
OK or NG
OK >> GO TO 6.
NG >> Replace malfunctioning heated oxygen sensor 2.
6. CHECK INTERMITTENT INCIDENT
Refer to EC-784, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionABS00C11
HEATED OXYGEN SENSOR 2 HEATER
1. Check resistance between HO2S2 terminals as follows.
2. If NG, replace heated oxygen sensor 2.
CAUTION:
Discard any heated oxygen sensor which has been dropped
from a height of more than 0.5 m (19.7 in) onto a hard sur-
face such as a concrete floor; use a new one.
Before installing new oxygen sensor, clean exhaust system
threads using Oxygen Sensor Thread Cleaner tool J-43897-
18 or J-43897-12 and approved anti-seize lubricant.
Removal and InstallationABS00C12
HEATED OXYGEN SENSOR 2
Refer to EM-178, "EXHAUST MANIFOLD AND THREE WAY CATALYST" .
Terminal No. Resistance
2 and 3 5.0 - 7.0 Ω at 25°C (77°F)
1 and 2, 3, 4
∞ Ω
(Continuity should not exist)
4 and 1, 2, 3
PBIB0970E
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![INFINITI FX35 2004 Service Manual EC-822
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DTC P0101 MAF SENSOR
Revision: 2004 November 2004 FX35/FX45
DTC P0101 MAF SENSORPFP:22680
Component DescriptionABS00C13
The mass air flow sensor is placed in the stream of intake air. INFINITI FX35 2004 Service Manual EC-822
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DTC P0101 MAF SENSOR
Revision: 2004 November 2004 FX35/FX45
DTC P0101 MAF SENSORPFP:22680
Component DescriptionABS00C13
The mass air flow sensor is placed in the stream of intake air.](/manual-img/42/57021/w960_57021-2162.png)
EC-822
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DTC P0101 MAF SENSOR
Revision: 2004 November 2004 FX35/FX45
DTC P0101 MAF SENSORPFP:22680
Component DescriptionABS00C13
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. It consists of a hot film that is supplied with electric current from
the ECM. The temperature of the hot film is controlled by the ECM a
certain amount. The heat generated by the hot film is reduced as the
intake air flows around it. The more air, the greater the heat loss.
Therefore, the ECM must supply more electric current to maintain
the temperature of the hot film as air flow increases. The ECM
detects the air flow by means of this current change.
CONSULT-II Reference Value in Data Monitor ModeABS00C14
Specification data are reference values.
On Board Diagnosis LogicABS00C15
This self-diagnosis has the one trip detection logic.
NOTE:
If DTC P0101 is displayed with DTC P1229, first perform the trouble diagnosis for DTC P1229. Refer to
EC-1156
.
SEC266C
MONITOR ITEM CONDITION SPECIFICATION
MAS A/F SE-B1 See EC-780, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
CAL/LD VALUE
Engine: After warming up
Air conditioner switch: OFF
Shift lever: N
No loadIdle 14% - 33%
2,500 rpm 12% - 25%
MASS AIRFLOW
Engine: After warming up
Air conditioner switch: OFF
Shift lever: N
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
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![INFINITI FX35 2004 Service Manual DTC P0101 MAF SENSOR
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DTC Confirmation ProcedureABS00C16
Perform PROCEDURE FOR MALFUNCTION A first.
If the DTC cannot be INFINITI FX35 2004 Service Manual DTC P0101 MAF SENSOR
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DTC Confirmation ProcedureABS00C16
Perform PROCEDURE FOR MALFUNCTION A first.
If the DTC cannot be](/manual-img/42/57021/w960_57021-2163.png)
DTC P0101 MAF SENSOR
EC-823
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DTC Confirmation ProcedureABS00C16
Perform PROCEDURE FOR MALFUNCTION A first.
If the DTC cannot be confirmed, perform PROCEDURE FOR MALFUNCTION B.
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 MALFUNCTION A
NOTE:
If engine will not start or stops soon, wait at least 10 seconds with engine stopped (Ignition switch ON) instead
of running engine at idle speed.
With CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Start engine and warm it up to normal operating temperature.
4. Run engine for at least 10 seconds at idle speed.
5. If DTC is detected, go to EC-826, "
Diagnostic Procedure" .
With GST
Follow the procedure “With CONSULT-II” above.
PROCEDURE FOR MALFUNCTION B
CAUTION:
Always drive vehicle at a safe speed.
With CONSULT-II
1. Turn ignition switch ON.
2. Start engine and warm it up to normal operating temperature.
If engine cannot be started, go to EC-826, "
Diagnostic Procedure" .
3. Select “DATA MONITOR” mode with CONSULT-II.
4. Check the voltage of “MAS A/F SE-B1” with “DATA MONITOR”.
5. Increases engine speed to about 4,000 rpm.
6. Monitor the linear voltage rise in response to engine speed
increases.
If NG, go to EC-826, "
Diagnostic Procedure" .
If OK, go to following step.
SEF174Y
SEF243Y
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![INFINITI FX35 2004 Service Manual EC-824
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DTC P0101 MAF SENSOR
Revision: 2004 November 2004 FX35/FX45
7. Maintain the following conditions for at least 10 consecutive sec-
onds.
8. If DTC is detected, go to EC-826, "
Diagnosti INFINITI FX35 2004 Service Manual EC-824
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DTC P0101 MAF SENSOR
Revision: 2004 November 2004 FX35/FX45
7. Maintain the following conditions for at least 10 consecutive sec-
onds.
8. If DTC is detected, go to EC-826, "
Diagnosti](/manual-img/42/57021/w960_57021-2164.png)
EC-824
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DTC P0101 MAF SENSOR
Revision: 2004 November 2004 FX35/FX45
7. Maintain the following conditions for at least 10 consecutive sec-
onds.
8. If DTC is detected, go to EC-826, "
Diagnostic Procedure" .
Overall Function CheckABS00C17
PROCEDURE FOR MALFUNCTION B
Use this procedure to check the overall function of the mass air flow sensor circuit. During this check, a DTC
might not be confirmed.
With GST
1. Start engine and warm it up to normal operating temperature.
2. Select MODE 1 with GST.
3. Check the mass air flow sensor signal with MODE 1.
4. Check for linear mass air flow sensor signal value rise in
response to increases to about 4,000 rpm in engine speed.
5. If NG, go to EC-826, "
Diagnostic Procedure" .
ENG SPEED More than 2,000 rpm
THRTL SEN 1 More than 3V
THRTL SEN 2 More than 3V
Selector lever Suitable position
Driving locationDriving vehicle uphill (Increased engine load) will help
maintain the driving conditions required for this test.
PBIB0199E
SEF534P
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DTC P0101 MAF SENSOR
EC-825
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Wiring DiagramABS00C18
TBWM0225E
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![INFINITI FX35 2004 Service Manual EC-826
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DTC P0101 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 te INFINITI FX35 2004 Service Manual EC-826
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DTC P0101 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 te](/manual-img/42/57021/w960_57021-2166.png)
EC-826
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DTC P0101 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 ProcedureABS00C19
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 to intake manifold
OK or NG
OK >> GO TO 3.
NG >> Reconnect the parts.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
48 LSensor power supply
(Mass air flow sensor)[Ignition switch: ON]Approximately 5V
51 L/W Mass air flow sensor[Engine is running]
Warm-up condition
Idle speed1.2 - 1.8V
[Engine is running]
Warm-up condition
Engine speed is 2,500 rpm1.7 - 2.4V
67 B/WSensor ground
(Mass air flow sensor / IAT
sensor / Power steering
pressure sensor / EVAP
control system pressure
sensor / Refrigerant pres-
sure sensor / ECT 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)
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3. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground scre INFINITI FX35 2004 Service Manual DTC P0101 MAF SENSOR
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3. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground scre](/manual-img/42/57021/w960_57021-2167.png)
DTC P0101 MAF SENSOR
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3. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-791, "
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 harness connector.
2. Turn ignition switch ON.
3. Check voltage between MAF sensor terminals 2, 4 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
Joint connector-3
Harness for open or short between IPDM E/R and mass air flow sensor
Harness for open or short between mass air flow sensor and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.
PBIB2195E
PBIB1502E
Terminal Voltage
2 Approximately 5V
4 Battery voltage
PBIB0076E