Nissan Frontier D40. Manual - part 402

P1226 TP SENSOR

EC-299

< COMPONENT DIAGNOSIS >

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C

D

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F

G

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A

EC

N

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2.

REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.

Replace the electric throttle control actuator.

2.

Perform 

EC-24, "Throttle Valve Closed Position Learning"

.

3.

Perform 

EC-24, "Idle Air Volume Learning"

.

>> INSPECTION END

EC-300

< COMPONENT DIAGNOSIS >

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P1421 COLD START CONTROL

P1421 COLD START CONTROL

Description

INFOID:0000000005273320

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:0000000005273321

DTC Confirmation Procedure

INFOID:0000000005273322

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.

• If DTC P1421 is displayed with other DTC, first perform the trouble diagnosis for other DTC.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V 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 steps.
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-300, "Diagnosis Procedure"

.

 WITH GST

Follow the procedure “WITH CONSULT-III” above.

Diagnosis Procedure

INFOID:0000000005273323

1.

PERFORM IDLE AIR VOLUME LEARNING

Perform 

EC-24, "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

3.

CHECK FUEL INJECTION SYSTEM FUNCTION

Perform 

EC-169, "DTC Confirmation Procedure"

 for DTC P0171.

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

P1421 COLD START CONTROL

EC-301

< COMPONENT DIAGNOSIS >

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OK or NG

OK

>> GO TO 4.

NG

>> Go to 

EC-170, "Diagnosis Procedure"

 for DTC P0171.

4.

PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT-III

1.

Turn ignition switch ON.

2.

Select “SELF DIAG RESULTS” mode with CONSULT-III.

3.

Touch “ERASE”.

4.

Perform DTC Confirmation Procedure.
See 

EC-300, "DTC Confirmation Procedure"

.

5.

Is the 1st trip DTC P1421 displayed again?

With GST

1.

Turn ignition switch ON.

2.

Select Service $04 with GST.

3.

Perform DTC Confirmation Procedure.
See 

EC-300, "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-7, "ECM RE-COMMUNICATING FUNCTION : Special Repair Requirement"

.

3.

Perform 

EC-24, "VIN Registration"

.

4.

Perform 

EC-24, "Accelerator Pedal Released Position Learning"

.

5.

Perform 

EC-24, "Throttle Valve Closed Position Learning"

.

6.

Perform 

EC-24, "Idle Air Volume Learning"

.

>> INSPECTION END

EC-302

< COMPONENT DIAGNOSIS >

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P1550 BATTERY CURRENT SENSOR

P1550 BATTERY CURRENT SENSOR

Component Description

INFOID:0000000005273324

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 is installed to the battery cable at the negative terminal.
The sensor measures the charging/discharging current of the bat-
tery. 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-6, "System

Description"

.

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:0000000005273325

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

EC-285

.

DTC Confirmation Procedure

INFOID:0000000005273326

If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V at idle.

 WITH CONSULT-III

1.

Start engine and wait at least 10 seconds.

2.

Check 1st trip DTC.

3.

If 1st trip DTC is detected, go to 

EC-302, "Diagnosis Procedure"

.

 WITH GST

Follow the procedure “WITH CONSULT-III” above.

Diagnosis Procedure

INFOID:0000000005273327

1.

CHECK GROUND CONNECTIONS

1.

Turn ignition switch OFF.

2.

Loosen and retighten two ground screws on the body.

BBIA0630E

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