Nissan Frontier. Manual - part 517

P0102, P0103 MAF SENSOR

EC-639

< DTC/CIRCUIT DIAGNOSIS >

[VQ40DE FOR USA AND CANADA]

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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 82.

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-635, "Component Inspection"

.

OK or NG

OK

>> GO TO 9.

NG

>> Replace mass air flow sensor. Refer to 

EM-141, "Exploded View"

.

9.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-42, "Intermittent Incident"

.

>> INSPECTION END

Component Inspection

INFOID:0000000009481280

MASS AIR FLOW SENSOR

 With CONSULT

1. Reconnect all harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.
3. Connect CONSULT and select “DATA MONITOR” mode.
4. Select “MAS A/F SE-B1” and check indication under the following 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.
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.

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*

EC-640

< DTC/CIRCUIT DIAGNOSIS >

[VQ40DE FOR USA AND CANADA]

P0102, P0103 MAF SENSOR

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

1. Reconnect all harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.
3. Check voltage between ECM terminal 82 (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.

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*

P0111 IAT SENSOR

EC-641

< DTC/CIRCUIT DIAGNOSIS >

[VQ40DE FOR USA AND CANADA]

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P0111 IAT SENSOR

Component Description

INFOID:0000000009481281

The intake air temperature sensor is built-into the mass air flow sen-

sor (1). 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 rise in temperature.

<Reference data>

*: These data are reference values and are measured between ECM terminals 74
(Intake air temperature sensor) and ground.

On Board Diagnosis Logic

INFOID:0000000009481282

DTC Confirmation Procedure

INFOID:0000000009481283

1.

INSPECTION START

Is it necessary to erase permanent DTC?

YES

>> GO TO 3.

NO

>> GO TO 2.

2.

PERFORM COMPONENT FUNCTION CHECK

Perform component function check. Refer to 

EC-642, "Component Function Check"

.

NOTE:

Use the component function check to check the overall function of the IAT sensor circuit. During this check, a

1st trip DTC might not be confirmed.
Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Proceed to 

EC-642, "Diagnosis Procedure"

.

PBIA9559J

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

(Trouble diagnosis content)

DTC detecting condition

Possible cause

P0111

IAT SENSOR 1 B1
[Intake air temperature (IAT) 
sensor circuit range/perfor-
mance]

The comparison result of signals transmitted 
to ECM from each temperature sensor (IAT 
sensor, ECT sensor, and FTT sensor) shows 
that the voltage signal of the IAT sensor is 
higher/lower than that of other temperature 
sensors when the engine is started with its 
cold state.

• Harness or connectors

(High or low resistance in the IAT sen-
sor circuit)

• IAT sensor

EC-642

< DTC/CIRCUIT DIAGNOSIS >

[VQ40DE FOR USA AND CANADA]

P0111 IAT SENSOR

3.

PRECONDITIONING

If DTC CONFIRMATION PROCEDURE has been previously conducted, always perform the following proce-

dure before conducting the next test.

1. Turn ignition switch OFF and wait at least 10 seconds.

2. Turn ignition switch ON.

3. Turn ignition switch OFF and wait at least 10 seconds.

TESTING CONDITION:

• Before performing the following procedure, do not add fuel.

• Before performing the following procedure, check that fuel level is between 1/4 and 4/4.

• Before performing the following procedure, confirm that battery voltage is 11 V or more at idle.

>> GO TO 4.

4.

PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine and let it idle for 60 minutes.

2. Move the vehicle to a cool place.

NOTE:

Cool the vehicle in an environment of ambient air temperature between 

−10°C (14°F) and 35°C (95°F).

3. Turn ignition switch OFF and soak the vehicle for 12 hours.

CAUTION:

Never turn ignition switch ON during soaking.

NOTE:

The vehicle must be cooled with the food open.

4. Start engine and let it idle for 5 minutes or more.

CAUTION:

Never turn ignition switch OFF during idling.

5. Check 1st trip DTC.
Is 1st trip DTC detected?

YES

>> Proceed to 

EC-642, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Component Function Check

INFOID:0000000009481284

1.

CHECK INTAKE AIR TEMPERATURE (IAT) SENSOR

1. Turn ignition switch OFF.

2. Disconnect mass air flow sensor harness connector.

3. Check resistance between mass air flow sensor terminals as follows.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Proceed to 

EC-642, "Diagnosis Procedure"

.

2.

CHECK INTERMITTENT INCIDENT

Check intermittent incident. Refer to 

GI-42, "Intermittent Incident"

.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Proceed to 

EC-642, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000009481285

1.

CHECK INTAKE AIR TEMPERATURE (IAT) SENSOR

Check intake air temperature sensor. Refer to 

EC-643, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 2.

Terminals

Condition

Resistance (k

Ω)

5 and 6

Temperature [

°C (°F)]

25 (77)

1.800 – 2.200