Nissan Frontier D22. Manual - part 259

DTC P0101 MAF SENSOR

EC-139

[KA24DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

Wiring Diagram

UBS00D2G

BBWA1055E

EC-140

[KA24DE]

DTC P0101 MAF SENSOR

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

UBS00D2H

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 followings for connection.

●

Air duct

●

Air cleaner

●

Vacuum hoses

●

Intake air passage between air duct to collector

OK or NG

OK

>> GO TO 3.

NG

>> Reconnect the parts.

3. 

RETIGHTEN GROUND SCREWS

1.

Turn ignition switch OFF.

2.

Loosen and retighten engine ground screws.

>> GO TO 4.

TER-

MINAL 

NO.

WIRE 

COLOR

ITEM

CONDITION

DATA (DC Voltage)

54

R

Mass air flow sensor

[Engine is running]

●

Warm-up condition

●

Idle speed

0.9 - 1.8V

[Engine is running]

●

Warm-up condition

●

Engine speed is 2,500 rpm

1.9 - 2.3V

55

G

Mass air flow sensor 
ground

[Engine is running]

●

Warm-up condition

●

Idle speed

Approximately 0V

BBIA0431E

DTC P0101 MAF SENSOR

EC-141

[KA24DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

4. 

CHECK POWER SUPPLY

1.

Disconnect mass air flow sensor harness connector.

2.

Turn ignition switch ON.

3.

Check voltage between 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 for open or short between ECM relay and mass air flow sensor

●

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

>>  Repair harness or connectors.

6. 

CHECK GROUND CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect ECM harness connector.

3.

Check harness continuity between mass air flow sensor terminal 3 and ECM terminal 55.
Refer to Wiring Diagram.

4.

Also check harness for short to ground or 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 INPUT SIGNAL CIRCUIT

1.

Check harness continuity between terminal 4 and ECM terminal 54.
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.

AEC131A

Voltage

: Battery voltage

SEF126V

Continuity should exist.

Continuity should exist.

EC-142

[KA24DE]

DTC P0101 MAF SENSOR

8. 

CHECK MASS AIR FLOW SENSOR

1.

Reconnect all harness connectors disconnected.

2.

Turn ignition switch ON.

3.

Start engine and warm it up to normal operating temperature.

4.

Check voltage between ECM terminal 54 (mass air flow sensor
signal) and ground.

*: Check for linear voltage rise in response to engine being increased to about
4,000 rpm.

5.

If the voltage is out of specification, disconnect mass air flow sensor harness connector and connect it
again. Repeat above check.

6.

If NG, remove mass air flow sensor from air duct. Check hot wire
for damage or dust.

OK or NG

OK

>> GO TO 9.

NG

>> Replace mass air flow sensor.

9. 

CHECK INTERMITTENT INCIDENT

Perform 

EC-120, "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT"

 .

>> INSPECTION END.

Condition

Voltage V

Ignition switch: ON (Engine stopped.)

Less than 1.0

Idle (Engine is warmed-up to normal operating 
temperature.)

0.9 - 185

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

1.9 - 2.3

Idle to about 4,000 rpm*

1.3 - 1.7 to Approx. 3.0

SEF326V

SEF893J