Nissan Pathfinder (2007 year). Manual - part 166

DTC P0101 MAF SENSOR

EC-195

C

D

E

F

G

H

I

J

K

L

M

A

EC

2007 Pathfinder

Removal and Installation

UBS00K5H

MASS AIR FLOW SENSOR

Refer to 

EM-16, "AIR CLEANER AND AIR DUCT"

  .

EC-196

DTC P0102, P0103 MAF SENSOR

2007 Pathfinder

DTC P0102, P0103 MAF SENSOR

PFP:22680

Component Description

UBS00K5I

The mass air flow sensor (1) is placed in the stream of intake air. It
measures 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 is 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 Mode

UBS00K5J

Specification data are reference values.

On Board Diagnosis Logic

UBS00K5K

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.

PBIA9559J

MONITOR ITEM

CONDITION

SPECIFICATION

MAS A/F SE-B1

See 

EC-135, "TROUBLE DIAGNOSIS - SPECIFICATION VALUE"

  .

CAL/LD VALUE

●

Engine: After warming up

●

Shift lever: P or N

●

Air conditioner switch: OFF

●

No load

Idle

5% - 35%

2,500 rpm

5% - 35%

MASS AIRFLOW

●

Engine: After warming up

●

Shift 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.

DTC P0102, P0103 MAF SENSOR

EC-197

C

D

E

F

G

H

I

J

K

L

M

A

EC

2007 Pathfinder

DTC Confirmation Procedure

UBS00K5L

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-199, "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-199, "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-199, "Diagnostic Procedure"

  .

 With GST

Follow the procedure “With CONSULT-II” above.

SEF058Y

SEF058Y

EC-198

DTC P0102, P0103 MAF SENSOR

2007 Pathfinder

Wiring Diagram

UBS00K5M

BBWA1922E

DTC P0102, P0103 MAF SENSOR

EC-199

C

D

E

F

G

H

I

J

K

L

M

A

EC

2007 Pathfinder

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 Procedure

UBS00K5N

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

●

Vacuum hoses

●

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

P

Mass air flow sensor

[Engine is running]

●

Warm-up condition

●

Idle speed

0.9 - 1.2V

[Engine is running]

●

Warm-up condition

●

Engine speed: 2,500 rpm

1.5 - 1.8V

67

B

Sensor ground

[Engine is running]

●

Warm-up condition

●

Idle speed

Approximately 0V

111

BR

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)

119

120

R
P

Power supply for ECM

[Ignition switch: ON]

BATTERY VOLTAGE
(11 - 14V)

EC-200

DTC P0102, P0103 MAF SENSOR

2007 Pathfinder

3. 

CHECK GROUND CONNECTIONS

1.

Turn ignition switch OFF.

2.

Loosen and retighten three ground screws on the body. Refer to 

EC-153, "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 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 E2, F32

●

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.

BBIA0539E

BBIA0541E

Voltage: Battery voltage

PBIB1168E

DTC P0102, P0103 MAF SENSOR

EC-201

C

D

E

F

G

H

I

J

K

L

M

A

EC

2007 Pathfinder

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-201, "Component Inspection"

  .

OK or NG

OK

>> GO TO 9.

NG

>> Replace mass air flow sensor.

9. 

CHECK INTERMITTENT INCIDENT

Refer to 

EC-145, "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT"

  .

>> INSPECTION END

Component Inspection

UBS00K5O

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.)

0.9 - 1.2

2,500 rpm (Engine is warmed-up to 
normal operating temperature.)

1.5 - 1.8

Idle to about 4,000 rpm

0.9 - 1.2 to Approx. 2.4*

PBIB2371E

EC-202

DTC P0102, P0103 MAF SENSOR

2007 Pathfinder

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 Installation

UBS00K5P

MASS AIR FLOW SENSOR

Refer to 

EM-16, "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.)

0.9 - 1.2

2,500 rpm (Engine is warmed-up to 
normal operating temperature.)

1.5 - 1.8

Idle to about 4,000 rpm

0.9 - 1.2 to Approx. 2.4*

PBIB1106E