Nissan Pathfinder (2009 year). Instruction — part 347

EC-790

< COMPONENT DIAGNOSIS >

[VK56DE]

P1225 TP SENSOR

P1225 TP SENSOR

Component Description

INFOID:0000000004333375

Electric throttle control actuator consists of throttle control motor,
throttle position sensor, etc. The throttle position sensor responds to
the throttle valve movement.
The throttle position sensor has the two sensors. These sensors are
a kind of potentiometer which transform the throttle valve position
into output voltage, and emit the voltage signals to the ECM. The
ECM judges the current opening angle of the throttle valve from
these signals and controls the throttle valve in response to driving
conditions via the throttle control motor.

On Board Diagnosis Logic

INFOID:0000000003936749

The MIL will not illuminate for this self-diagnosis.

DTC Confirmation Procedure

INFOID:0000000003936750

NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next step.
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, confirm that battery voltage is more than 10 V at idle.
1.

Turn ignition switch ON.

2.

Turn ignition switch OFF and wait at least 10 seconds.

3.

Turn ignition switch ON.

4.

Check 1st trip DTC.

5.

If 1st trip DTC is detected, go to

EC-790, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000003936751

1.

CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY

1.

Turn ignition switch OFF.

2.

Remove the intake air duct.

3.

Check if foreign matter is caught between the throttle valve and
the housing.

OK or NG

OK

>> GO TO 2.

NG

>> Remove the foreign matter and clean the electric throttle

control actuator inside.

2.

REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

PBIB0145E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P1225
1225

Closed throttle position learning
performance

Closed throttle position learning value is
excessively low.

• Electric throttle control actuator

(TP sensor 1 and 2)

BBIA0371E

2009 Pathfinder

P1225 TP SENSOR

EC-791

< COMPONENT DIAGNOSIS >

[VK56DE]

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1.

Replace the electric throttle control actuator.

2.

Perform

EC-500, "Throttle Valve Closed Position Learning"

.

3.

Perform

EC-500, "Idle Air Volume Learning"

.

>> INSPECTION END

2009 Pathfinder

EC-792

< COMPONENT DIAGNOSIS >

[VK56DE]

P1226 TP SENSOR

P1226 TP SENSOR

Component Description

INFOID:0000000004333377

Electric throttle control actuator consists of throttle control motor,
throttle position sensor, etc. The throttle position sensor responds to
the throttle valve movement.
The throttle position sensor has the two sensors. These sensors are
a kind of potentiometer which transform the throttle valve position
into output voltage, and emit the voltage signals to the ECM. The
ECM judges the current opening angle of the throttle valve from
these signals and controls the throttle valve in response to driving
conditions via the throttle control motor.

On Board Diagnosis Logic

INFOID:0000000003936753

The MIL will not illuminate for this self-diagnosis.

DTC Confirmation Procedure

INFOID:0000000003936754

NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next step.
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, confirm that battery voltage is more than 10 V at idle.

1.

Turn ignition switch ON.

2.

Turn ignition switch OFF and wait at least 10 seconds.

3.

Turn ignition switch ON.

4.

Repeat steps 2 and 3 for 32 times.

5.

Check 1st trip DTC.

6.

If 1st trip DTC is detected, go to

EC-792, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000004333378

1.

CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY

1.

Turn ignition switch OFF.

2.

Remove the intake air duct.

3.

Check if foreign matter is caught between the throttle valve and
the housing.

OK or NG

OK

>> GO TO 2.

NG

>> Remove the foreign matter and clean the electric throttle

control actuator inside.

PBIB0145E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P1226
1226

Closed throttle position learning
performance

Closed throttle position learning is not performed
successfully, repeatedly.

• Electric throttle control actuator

(TP sensor 1 and 2)

BBIA0371E

2009 Pathfinder

P1226 TP SENSOR

EC-793

< COMPONENT DIAGNOSIS >

[VK56DE]

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2.

REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.

Replace the electric throttle control actuator.

2.

Perform

EC-500, "Throttle Valve Closed Position Learning"

.

3.

Perform

EC-500, "Idle Air Volume Learning"

.

>> INSPECTION END

2009 Pathfinder

EC-794

< COMPONENT DIAGNOSIS >

[VK56DE]

P1421 COLD START CONTROL

P1421 COLD START CONTROL

Description

INFOID:0000000003936756

ECM controls ignition timing and engine idle speed when engine is started with prewarming up condition.
This control promotes the activation of three way catalyst by heating the catalyst and reduces emissions.

On Board Diagnosis Logic

INFOID:0000000003936757

If DTC P1421 is displayed with other DTC, first perform the trouble diagnosis for other DTC.

DTC Confirmation Procedure

INFOID:0000000003936758

NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next step.
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, confirm that battery voltage is more than 11 V at idle.

WITH CONSULT-III

1.

Turn ignition switch OFF and wait at least 10 seconds.

2.

Turn ignition switch ON.

3.

Select “DATA MONITOR” mode with CONSULT-III.

4.

Check that the “COOLAN TEMP/S” indication is between 4

°

C (39

°

F) and 36

°

C (97

°

F).

If “COOLAN TEMP/S” indication is within the specified value, go to the following step.
If “COOLAN TEMP/S” indication is out of the specified value, cool engine down or warm engine up and go
to step 1.

5.

Start engine and let it idle for 5 minutes.

6.

Check 1st trip DTC.

7.

If 1st trip DTC is detected, go to

EC-794, "Diagnosis Procedure"

.

WITH GST

Follow the procedure “WITH CONSULT-III” above.

Diagnosis Procedure

INFOID:0000000003936759

1.

PERFORM IDLE AIR VOLUME LEARNING

Perform

EC-500, "Idle Air Volume Learning"

.

Is Idle Air Volume Learning carried out successfully?

Yes or No

Yes

>> GO TO 2.

No

>> Follow the instruction of Idle Air Volume Learning.

2.

CHECK INTAKE SYSTEM

Check for the cause of intake air volume lacking. Refer to the following.
• Crushed intake air passage
• Intake air passage clogging

OK or NG

OK

>> GO TO 3.

NG

>> Repair or replace malfunctioning part

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P1421
1421

Cold start emission reduction
strategy monitoring

ECM does not control ignition timing and engine
idle speed properly when engine is started with
prewarming up condition.

• Lack of intake air volume
• Fuel injection system
• ECM

2009 Pathfinder

P1421 COLD START CONTROL

EC-795

< COMPONENT DIAGNOSIS >

[VK56DE]

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3.

CHECK FUEL INJECTION SYSTEM FUNCTION

Perform

EC-657, "DTC Confirmation Procedure"

in DTC P0171, P0174 FUEL INJECTION SYSTEM FUNC-

TION.

OK or NG

OK

>> GO TO 4.

NG

>> Go to

EC-659, "Diagnosis Procedure"

.

4.

PERFORM DTC CONFIRMATION PROCEDURE

1.

Turn ignition switch ON.

2.

Erase DTC. Refer to

EC-525, "Emission-related Diagnostic Information"

.

3.

Perform DTC Confirmation Procedure. Refer to

EC-794, "DTC Confirmation Procedure"

.

4.

Is the 1st trip DTC P1421 displayed again?

Yes or No

Yes

>> GO TO 5.

No

>> INSPECTION END

5.

REPLACE ECM

1.

Replace ECM.

2.

Perform initialization of NVIS (NATS) system and registration of all NVIS (NATS) ignition key IDs.
Refer to

SEC-8, "ECM RE-COMMUNICATING FUNCTION : Special Repair Requirement"

(with intelligent

key system) or

SEC-124, "ECM RE-COMMUNICATING FUNCTION : Special Repair Requirement"

(with-

out intelligent key system).

3.

Perform

EC-499, "VIN Registration"

.

4.

Perform

EC-500, "Accelerator Pedal Released Position Learning"

.

5.

Perform

EC-500, "Throttle Valve Closed Position Learning"

.

6.

Perform

EC-500, "Idle Air Volume Learning"

.

>> INSPECTION END

2009 Pathfinder

EC-796

< COMPONENT DIAGNOSIS >

[VK56DE]

P1550 BATTERY CURRENT SENSOR

P1550 BATTERY CURRENT SENSOR

Component Description

INFOID:0000000003936760

The power generation voltage variable control enables fuel con-
sumption to be decreased by reducing the engine load which is
caused by the power generation of the generator. The battery cur-
rent sensor (1) is installed to the battery cable at the negative termi-
nal. The sensor measures the charging/discharging current of the
battery. Based on the sensor signal, ECM judges whether or not the
power generation voltage variable control is performed. When per-
forming the power generation voltage variable control, ECM calcu-
lates the target power generation voltage based on the sensor
signal. And ECM sends the calculated value as the power genera-
tion command value to IPDM E/R. For the details of the power gen-
eration voltage variable control, refer to

CHG-7, "System

Description"

.

: Vehicle front

CAUTION:

Never connect the electrical component or the ground wire directly to the battery terminal. The con-
nection causes the malfunction of the power generation voltage variable control, and then the battery
discharge may occur.

On Board Diagnosis Logic

INFOID:0000000003936761

The MIL will not illuminate for this self-diagnosis.
NOTE:
If DTC P1550 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643. Refer to

EC-775, "DTC Confirmation Procedure"

.

DTC Confirmation Procedure

INFOID:0000000003936762

NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next step.
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, confirm that battery voltage is more than 8 V at idle.

1.

Start engine and wait at least 10 seconds.

2.

Check 1st trip DTC.

3.

If 1st trip DTC is detected, go to

EC-796, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000003936763

1.

CHECK GROUND CONNECTIONS

1.

Turn ignition switch OFF.

2.

Loosen and retighten ground screws on the body.

ALBIA0362ZZ

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P1550
1550

Battery current sensor circuit
range/performance

The output voltage of the battery current
sensor remains within the specified
range while engine is running.

• Harness or connectors

(The sensor circuit is open or shorted.)

• Battery current sensor

2009 Pathfinder

P1550 BATTERY CURRENT SENSOR

EC-797

< COMPONENT DIAGNOSIS >

[VK56DE]

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Refer to

EC-568, "Ground Inspection"

.

OK or NG

OK

>> GO TO 2.

NG

>> Repair or replace ground connections.

2.

CHECK BATTERY CURRENT SENSOR POWER SUPPLY CIRCUIT

1.

Disconnect battery current sensor (1) harness connector.

2.

Turn ignition switch ON.

: Vehicle front

3.

Check voltage between battery current sensor terminal 1 and
ground with CONSULT-III or tester.

OK or NG

OK

>> GO TO 4.

NG

>> GO TO 3.

3.

DETECT MALFUNCTIONING PART

Check the following.
• Harness connectors E5, F14
• Harness for open or short between battery current sensor and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

4.

CHECK BATTERY CURRENT SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1.

Turn ignition switch OFF.

2.

Disconnect ECM harness connector.

3.

Check harness continuity between battery current sensor terminal 2 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 6.

NG

>> GO TO 5.

BBIA0539E

ALBIA0362ZZ

Voltage: Approximately 5 V

PBIA9891J

Continuity should exist.

2009 Pathfinder