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Infiniti Q45 (FY33). Manual - part 190

SEF643Q

EGR temperature sensor

Check resistance change and resistance value.

EGR temperature

°C (°F)

Voltage*

(V)

Resistance

Ω

)

0 (32)

4.61

0.68 - 1.11

50 (122)

2.53

0.09 - 0.12

100 (212)

0.87

0.017 - 0.024

If NG, replace EGR temperature sensor.

SEF320U

SEF083P

EGRC-BPT valve

Plug one of two ports of EGRC-BPT valve.

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

O, 3.94 inH

from under EGRC-BPT valve.

If a leakage is noted, replace the valve.

IDX

TROUBLE DIAGNOSIS FOR DTC P0400

EGR Function (Close) (Cont’d)

EC-289

EGRC-BPT Valve Function

SEF091PI

SYSTEM DESCRIPTION

The EGRC-BPT valve monitors exhaust pressure to activate the diaphragm, controlling throttle body vacuum
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

If too much EGR flow exists due to an EGRC-BPT valve malfunction, off idle engine roughness will increase.
If the roughness is excessive, 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.

Diagnostic Trouble

Code No.

Malfunction is detected when ...

Check Items

(Possible Cause)

P0402
0306

The EGRC-BPT valve does not operate properly.

EGRC-BPT valve

EGR valve

Loose or disconnected rubber tube

Blocked rubber tube

Camshaft position sensor

Blocked exhaust system

Orifice

Mass air flow sensor

EGRC-solenoid valve

TROUBLE DIAGNOSIS FOR DTC P0402

EC-290

SEF930V

SEC044C

SEC045C

SEC046C

PEF034W

DIAGNOSTIC TROUBLE CODE CONFIRMATION
PROCEDURE

CAUTION:

Always drive vehicle at a safe speed.
NOTE:
If “DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCE-
DURE” has been previously conducted, always turn ignition
switch “OFF” and wait at least 5 seconds before conducting
the next test.
TESTING CONDITION:

For best results, perform the test at temperature above
5°C (41°F) or higher.

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

1) Install vacuum gauge between EGRC-BPT valve and

EGR valve as shown in the figure.

2) Start engine and warm it up to normal operating tem-

perature.

3) Stop engine and wait at least 5 seconds.
4) Turn ignition switch “ON” and select “EGRC-BPT/V

P0402” of “EGR SYSTEM” in “DTC WORK SUPPORT”
mode with CONSULT-II.

5) Start engine (TCS switch “OFF”) and let it idle.
6) Touch “START”.
7) Check the output voltage of “THRTL POS SEN” at

closed throttle position and open throttle position.

8) When the following conditions are met, “TESTING” will

be displayed on the CONSULT-II screen and the bar
chart may increase. Maintain the conditions many times
until “COMPLETED” appears.
Selector lever: Suitable position
CMPS-RPM (POS): 1,000 - 1,600 rpm
Vehicle speed: 30 - 56 km/h (19 - 35 MPH)
B/FUEL SCHDL: 2.0 - 3.2 msec
THRTL POS SEN: X − (X + 0.89) V

X = Voltage value measured at

step 7)

The bar chart on CONSULT-II screen indicates the
status of this test. However, the test may be fin-
ished 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 4).
If NG, go to “DIAGNOSTIC PROCEDURE”, EC-293.
If OK, go to next step.

9) Open engine hood.
10) Raise engine speed to 2,000 to 2,800 rpm under no-

load and hold it. Then touch “NEXT” of the CONSULT-II
screen.

11) Check vacuum gauge while keeping engine speed

2,000 to 2,800 rpm.
Vacuum should be 0 to −20.0 kPa (0 to −150 mmHg,
0 to −5.91 inHg).
If NG, go to “DIAGNOSTIC PROCEDURE”, EC-293.
If OK, touch “YES” in the CONSULT-II screen.

IDX

TROUBLE DIAGNOSIS FOR DTC P0402

EGRC-BPT Valve Function (Cont’d)

EC-291

PEF035W

12) Check the rubber tube between intake manifold

collector,

EGR

valve

and

EGRC-BPT

valve

for

misconnection, cracks, blockages or twisting.
If NG, repair.
If OK, touch “YES” in the CONSULT-II screen.

13) If CONSULT-II instructs to carry out “OVERALL FUNC-

TION CHECK”, go to next step. If “NG” is displayed,
refer to “DIAGNOSTIC PROCEDURE”, EC-293.

SEF930V

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ OR ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

OVERALL FUNCTION CHECK

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

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

Lift up vehicle.

Connect the intake manifold collector and the EGRC-BPT
valve with a rubber tube that has 0.5 mm (0.020 in) dia. orifice.
(The intake manifold vacuum will be directly applied to the
EGRC-BPT valve.)

Start engine and shift to 1st position.

Check vacuum gauge while keeping engine speed 2,400±400
rpm.
Vacuum should be 0 to −20.0 kPa (0 to −150 mmHg, 0 to
−5.91 inHg).
If NG, go to “DIAGNOSTIC PROCEDURE”, EC-293.
If OK, go to next step.

Check rubber tube between the intake manifold collector,
EGRC-solenoid

valve

and

EGRC-BPT

valve

for

misconnection, cracks, blockages or twisting.

If NG, repair or replace.

TROUBLE DIAGNOSIS FOR DTC P0402

EGRC-BPT Valve Function (Cont’d)

EC-292

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