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EC-42Revision: October 2005
ON BOARD REFUELING VAPOR RECOVERY (ORVR)
2005 QX56
7. CHECK REFUELING EVAP VAPOR CUT VALVE
Refer to EC-43, "
Component Inspection" .
OK or NG
OK >> GO TO 8.
NG >> Replace refueling EVAP vapor cut valve with fuel tank.
8. CHECK FUEL FILLER TUBE
Check filler neck tube and hose connected to the fuel tank for clogging, dents and cracks.
OK or NG
OK >> GO TO 9.
NG >> Replace fuel filler tube.
9. CHECK ONE-WAY FUEL VALVE-I
Check one-way valve for clogging.
OK or NG
OK >> GO TO 10.
NG >> Repair or replace one-way fuel valve with fuel tank.
10. CHECK ONE-WAY FUEL VALVE-II
1. Make sure that fuel is drained from the tank.
2. Remove fuel filler tube and hose.
3. Check one-way fuel valve for operation as follows.
When a stick is inserted, the valve should open, when removing
stick it should close.
Do not drop any material into the tank.
OK or NG
OK >>INSPECTION END
NG >> Replace fuel filler tube or replace one-way fuel valve
with fuel tank.
SEF 6 65 U
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ON BOARD REFUELING VAPOR RECOVERY (ORVR)
EC-43
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Component InspectionUBS00KZL
REFUELING EVAP VAPOR CUT VALVE
With CONSULT-II
1. Remove fuel tank. Refer to FL-9, "FUEL TANK" .
2. Drain fuel from the tank as follows:
a. Remove fuel feed hose located on the fuel gauge retainer.
b. Connect a spare fuel hose, one side to fuel gauge retainer where the hose was removed and the other
side to a fuel container.
c. Drain fuel using “FUEL PUMP RELAY” in “ACTIVE TEST” mode with CONSULT-II.
3. Check refueling EVAP vapor cut valve for being stuck to close as follows.
Blow air into the refueling EVAP vapor cut valve (from the end of EVAP/ORVR line hose), and check that
the air flows freely into the tank.
4. Check refueling EVAP vapor cut valve for being stuck to open as follows.
a. Connect vacuum pump to hose end.
b. Remove fuel gauge retainer with fuel gauge unit.
Always replace O-ring with new one.
c. Put fuel tank upside down.
d. Apply vacuum pressure to hose end [−13.3 kPa (−100 mmHg, −3.94 inHg)] with fuel gauge retainer
remaining open and check that the pressure is applicable.
Without CONSULT-II
1. Remove fuel tank. Refer to FL-9, "FUEL TANK" .
2. Drain fuel from the tank as follows:
a. Remove fuel gauge retainer.
b. Drain fuel from the tank using a handy pump into a fuel container.
3. Check refueling EVAP vapor cut valve for being stuck to close as follows.
Blow air into the refueling EVAP vapor cut valve (from the end of EVAP/ORVR line hose), and check that
the air flows freely into the tank.
4. Check refueling EVAP vapor cut valve for being stuck to open as follows.
a. Connect vacuum pump to hose end.
b. Remove fuel gauge retainer with fuel gauge unit.
Always replace O-ring with new one.
c. Put fuel tank upside down.
BBIA0401E
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EC-44Revision: October 2005
ON BOARD REFUELING VAPOR RECOVERY (ORVR)
2005 QX56
d. Apply vacuum pressure to hose end [−13.3 kPa (−100 mmHg, −3.94 inHg)] with fuel gauge retainer
remaining open and check that the pressure is applicable.
BBIA0401E
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POSITIVE CRANKCASE VENTILATION
EC-45
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POSITIVE CRANKCASE VENTILATIONPFP:11810
DescriptionUBS00KZM
SYSTEM DESCRIPTION
This system returns blow-by gas to the intake manifold.
The positive crankcase ventilation (PCV) valve is provided to conduct crankcase blow-by gas to the intake
manifold. During partial throttle operation of the engine, the intake manifold sucks the blow-by gas through the
PCV valve. Normally, the capacity of the valve is sufficient to handle any blow-by and a small amount of venti-
lating air. The ventilating air is then drawn from the air inlet tubes into the crankcase. In this process the air
passes through the hose connecting air inlet tubes to rocker cover. Under full-throttle condition, the manifold
vacuum is insufficient to draw the blow-by flow through the valve. The flow goes through the hose connection
in the reverse direction.
On vehicles with an excessively high blow-by, the valve does not
meet the requirement. This is because some of the flow will go
through the hose connection to the air inlet tubes under all condi-
tions.
Component InspectionUBS00KZN
PCV (POSITIVE CRANKCASE VENTILATION) VALVE
With engine running at idle, remove PCV valve from rocker cover. A
properly working valve makes a hissing noise as air passes through
it. A strong vacuum should be felt immediately when a finger is
placed over valve inlet.
PBIB0062E
PBIB1588E
PBIB1589E
Page 1237 of 3419
EC-46Revision: October 2005
POSITIVE CRANKCASE VENTILATION
2005 QX56
PCV VALVE VENTILATION HOSE
1. Check hoses and hose connections for leaks.
2. Disconnect all hoses and clean with compressed air. If any hose
cannot be freed of obstructions, replace.
S-ET 27 7
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IVIS (INFINITI VEHICLE IMMOBILIZER SYSTEM-NATS)
EC-47
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IVIS (INFINITI VEHICLE IMMOBILIZER SYSTEM-NATS)PFP:28591
DescriptionUBS00L1L
If the security indicator lights up with the ignition switch in
the ON position or “NATS MALFUNCTION” is displayed on
“SELF-DIAG RESULTS” screen, perform self-diagnostic
results mode with CONSULT-II using NATS program card.
Refer to BL-137, "
IVIS (INFINITI VEHICLE IMMOBILIZER
SYSTEM-NATS)" .
Confirm no self-diagnostic results of IVIS (NATS) is dis-
played before touching “ERASE” in “SELF-DIAG RESULTS”
mode with CONSULT-II.
When replacing ECM, initialization of IVIS (NATS) system
and registration of all IVIS (NATS) ignition key IDs must be
carried out with CONSULT-II using NATS program card.
Therefore, be sure to receive all keys from vehicle owner. Regarding the procedures of IVIS (NATS)
initialization and IVIS (NATS) ignition key ID registration, refer to CONSULT-II operation manual,
IVIS/NVIS.
SEF 5 43 X
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EC-48Revision: October 2005
ON BOARD DIAGNOSTIC (OBD) SYSTEM
2005 QX56
ON BOARD DIAGNOSTIC (OBD) SYSTEMPFP:00028
IntroductionUBS00KZP
The ECM has an on board diagnostic system, which detects malfunctions related to engine sensors or actua-
tors. The ECM also records various emission-related diagnostic information including:
The above information can be checked using procedures listed in the table below.
×: Applicable —: Not applicable
*: When DTC and 1st trip DTC simultaneously appear on the display, they cannot be clearly distinguished from each other.
The malfunction indicator lamp (MIL) on the instrument panel lights up when the same malfunction is detected
in two consecutive trips (Two trip detection logic), or when the ECM enters fail-safe mode. (Refer to EC-103,
"Fail-safe Chart" .)
Two Trip Detection LogicUBS00KZQ
When a malfunction is detected for the first time, 1st trip DTC and 1st trip Freeze Frame data are stored in the
ECM memory. The MIL will not light up at this stage. <1st trip>
If the same malfunction is detected again during the next drive, the DTC and Freeze Frame data are stored in
the ECM memory, and the MIL lights up. The MIL lights up at the same time when the DTC is stored. <2nd
trip> The “trip” in the “Two Trip Detection Logic” means a driving mode in which self-diagnosis is performed
during vehicle operation. Specific on board diagnostic items will cause the ECM to light up or blink the MIL,
and store DTC and Freeze Frame data, even in the 1st trip, as shown below.
×: Applicable —: Not applicable
When there is an open circuit on MIL circuit, the ECM cannot warn the driver by lighting up MIL when there is
malfunction on engine control system.
Emission-related diagnostic information Diagnostic service
Diagnostic Trouble Code (DTC) Service $03 of SAE J1979
Freeze Frame data Service $02 of SAE J1979
System Readiness Test (SRT) code Service $01 of SAE J1979
1st Trip Diagnostic Trouble Code (1st Trip DTC) Service $07 of SAE J1979
1st Trip Freeze Frame data
Test values and Test limits Service $06 of SAE J1979
Calibration ID Service $09 of SAE J1979
DTC 1st trip DTCFreeze
Frame data1st trip Freeze
Frame dataSRT code SRT status Test value
CONSULT-II×× × × × ×—
GST×× ×—×××
ECM××*— — —×—
ItemsMIL DTC 1st trip DTC
1st trip 2nd trip
1st trip
displaying2nd trip
displaying1st trip
displaying2nd trip
display-
ing BlinkingLighting
upBlinkingLighting
up
Misfire (Possible three way cata-
lyst damage) — DTC: P0300 -
P0308 is being detected×———— —×—
Misfire (Possible three way cata-
lyst damage) — DTC: P0300 -
P0308 is being detected——×——×——
One trip detection diagnoses
(Refer to EC-49, "
EMISSION-
RELATED DIAGNOSTIC INFOR-
MATION ITEMS" .)—×——×———
Except above — — —×—××—
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ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-49
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Therefore, when electrical controlled throttle and part of ECM related diagnoses are continuously detected as
NG for 5 trips, ECM warns the driver that engine control system malfunctions and MIL circuit is open by means
of operating fail-safe function.
The fail-safe function also operates when above diagnoses except MIL circuit are detected and demands the
driver to repair the malfunction.
Emission-related Diagnostic InformationUBS00KZR
EMISSION-RELATED DIAGNOSTIC INFORMATION ITEMS
×:Applicable —: Not applicable Engine operating condition in fail-safe mode Engine speed will not rise more than 2,500 rpm due to the fuel cut
Items
(CONSULT-II screen terms)DTC*
1
SRT codeTe s t v a l u e /
Test limit
(GST only)Trip MILRefer-
ence page CONSULT-II
GST*
2ECM*3
CAN COMM CIRCUIT U1000
1000*5—— 1×EC-163
CAN COMM CIRCUIT U1001
1001*5—— 2 —EC-163
NO DTC IS DETECTED.
FURTHER TESTING
MAY BE REQUIRED.P0000 0000———
Flashing*7EC-65
HO2S2 HTR (B1) P0037 0037××2×EC-166
HO2S2 HTR (B1) P0038 0038××2×EC-166
HO2S2 HTR (B2) P0057 0057××2×EC-166
HO2S2 HTR (B2) P0058 0058××2×EC-166
MAF SEN/CIRCUIT P0101 0101 — — 2×EC-174
MAF SEN/CIRCUIT P0102 0102 — — 1×EC-183
MAF SEN/CIRCUIT P0103 0103 — — 1×EC-183
IAT SEN/CIRCUIT P0112 0112 — — 2×EC-191
IAT SEN/CIRCUIT P0113 0113 — — 2×EC-191
ECT SEN/CIRCUIT P0117 0117 — — 1×EC-195
ECT SEN/CIRCUIT P0118 0118 — — 1×EC-195
TP SEN 2/CIRC P0122 0122 — — 1×EC-201
TP SEN 2/CIRC P0123 0123 — — 1×EC-201
ECT SENSOR P0125 0125 — — 1×EC-208
IAT SENSOR P0127 0127 — — 2×EC-211
THERMSTAT FNCTN P0128 0128 — — 2×EC-214
HO2S2 (B1) P0138 0138 —×2×EC-216
HO2S2 (B1) P0139 0139××2×EC-225
HO2S2 (B2) P0158 0158 —×2×EC-216
HO2S2 (B2) P0159 0159××2×EC-225
FUEL SYS-LEAN-B1 P0171 0171 — — 2×EC-236
FUEL SYS-RICH-B1 P0172 0172 — — 2×EC-245
FUEL SYS-LEAN-B2 P0174 0174 — — 2×EC-236
FUEL SYS-RICH-B2 P0175 0175 — — 2×EC-245
FTT SENSOR P0181 0181 — — 2×EC-253
FTT SEN/CIRCUIT P0182 0182 — — 2×EC-259
FTT SEN/CIRCUIT P0183 0183 — — 2×EC-259
TP SEN 1/CIRC P0222 0222 — — 1×EC-264
TP SEN 1/CIRC P0223 0223 — — 1×EC-264
MULTI CYL MISFIRE P0300 0300 — — 2×EC-271