Nissan Frontier D22. Manual - part 445

DTC P0400 EGR FUNCTION

EC-883

[VG33E]

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12. 

CHECK INTERMITTENT INCIDENT

Refer to 

EC-696, "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT"

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>> INSPECTION END.

Component Inspection

UBS00DK4

EGR VALVE

1.

Apply vacuum to EGR vacuum port with a hand vacuum pump.

2.

Check for sticking.

3.

If NG, repair or replace EGR valve.

EGRC-BPT VALVE

1.

Plug one of two ports of EGRC-BPT valve.

2.

Vacuum from the other port and check for leakage while apply-
ing a pressure above 0.981 kPa (100 mmH

2

  O,  3.94  inH

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 O)

from under EGRC-BPT valve.

3.

If a leakage is noted, replace the valve.

Removal and Installation

UBS00DK5

EGR VALVE

Refer to 

EM-80, "OUTER COMPONENT PARTS"

 .

EGR valve spring should lift.

MEF137D

SEF083P

EC-884

[VG33E]

DTC P0402 EGRC-BPT VALVE FUNCTION

DTC P0402 EGRC-BPT VALVE FUNCTION

PFP:14741

Description

UBS00DK6

SYSTEM DESCRIPTION

The EGRC-BPT valve monitors exhaust pressure to activate the diaphragm, controlling intake manifold vac-
uum applied to the EGR valve. In other words, recirculated exhaust gas is controlled in response to positioning
of the EGR valve or to engine operation.

On Board Diagnosis Logic

UBS00DK7

If too much EGR flow exists due to an EGRC-BPT valve malfunction, off idle engine roughness will increase. If
the roughness is large, then the vacuum to the EGR valve is interrupted through the EGRC-solenoid valve. If
the engine roughness is reduced at that time, the EGRC-BPT valve malfunction is indicated.

DTC Confirmation Procedure

UBS00DK8

CAUTION:

Always drive vehicle at a safe speed.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 5 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.

SEF864U

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible Cause

P0402

ECRC-BPT VALVE FUNCTION

●

The EGRC-BPT valve does not 
operate properly.

●

EGRC-BPT valve

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EGR valve

●

Loose or disconnected rubber tube

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Blocked rubber tube

●

Camshaft position sensor

●

Blocked exhaust system

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Orifice

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Mass air flow sensor

●

EGRC-solenoid valve

DTC P0402 EGRC-BPT VALVE FUNCTION

EC-885

[VG33E]

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 WITH CONSULT-II

1.

Install vacuum gauge between EGRC-BPT valve and EGR
valve as shown in the illustration.

2.

Start engine and warm it up to normal operating temperature.

3.

Stop engine and wait at least 5 seconds.

4.

Turn ignition switch ON and select “EGRC-BPT VLV P0402” of
“EGR SYSTEM” in “DTC WORK SUPPORT” mode with CON-
SULT-II.

5.

Start engine and let it idle.

6.

Touch “START”.

7.

Check the output voltage of “THRTL POS SEN” (at closed throt-
tle position) and note it.

8.

When the following conditions are met, “TESTING” will be dis-
played on the CONSULT-II screen and the bar chart may
increase. Maintain the conditions many times until “COM-
PLETED” appears.

NOTE:

●

The bar chart on CONSULT-II screen indicates the status
of this test. However, the test may be finished before the
bar chart becomes full scale.

●

If the bar chart indication does not continue to progress,
completely release accelerator pedal once and try to
meet the conditions again.

●

If “TESTING” does not appear on CONSULT-II screen,
retry from step 2.

9.

If CONSULT-II instructs to carry out Overall Function Check, go
to next step. If “NG” is displayed, refer to 

EC-887, "Diagnostic

Procedure"

 .

10. Open engine hood.

SEF930VA

SEF718Z

Selector lever

Suitable position

ENG SPEED

1,000 - 1,600 rpm

Vehicle speed

30 - 60 km/h (19 - 37 MPH) (A/T models)
30 - 100 km/h (19 - 62 MPH) (M/T models)

B/FUEL SCHDL

3.5 - 5.2 msec

THRTL POS SEN

X – (X + 0.9) V
X = Voltage value measured at step 7

SEF719Z

LEC038A

EC-886

[VG33E]

DTC P0402 EGRC-BPT VALVE FUNCTION

11. Raise engine speed to 2,000 to 2,800 rpm under no-load and

hold it. Then touch “NEXT” on CONSULT-II screen.

12. Check vacuum gauge while keeping engine speed at 2,000 to

2,800 rpm.
Vacuum should be 0 to 

−20 kPa (0 to −150 mmHg, 0 to −5.91

inHg).
If NG, go to 

EC-887, "Diagnostic Procedure"

 .

If OK, touch “YES” on the CONSULT-II screen.

13. Check the rubber tube between intake manifold collector,

EGRC-solenoid valve, EGR valve and EGRC-BPT valve for
cracks, blockages or twisting.
If NG, repair or replace.
If OK, touch “YES” on the CONSULT-II screen.

Overall Function Check

UBS00DK9

Use this procedure to check the overall function of the EGRC-BPT valve. During this check, a 1st trip DTC
might not be confirmed.

 WITH GST

1.

Install vacuum gauge between EGRC-BPT valve and EGR
valve as shown in the illustration.

2.

Lift up vehicle.

3.

Start engine and shift to 1st gear position.

4.

Check vacuum gauge while keeping engine speed at 2,000 to
2,800 rpm.
Vacuum should be 0 to 

−20 kPa (0 to −150 mmHg, 0 to −5.91

inHg).
If NG, go to 

EC-887, "Diagnostic Procedure"

 .

If OK, go to next step.

5.

Check rubber tube between intake manifold collector, EGRC-
solenoid valve, EGR valve and EGRC-BPT valve for misconnection, cracks or blockages.

6.

If NG, go to 

EC-887, "Diagnostic Procedure"

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PEF034W

PEF035W

SEF930V