2001 INFINITI QX4 IDX

DescriptionNBEC0221SYSTEM DESCRIPTIONNBEC0221S01
Sensor Input Signal to ECMECM
functionActuator
Crankshaft position sensor (POS) Engine speed (POS signal)
EVAP can-
ister purge
flow controlEVAP canister purge volume
control solenoid valve Crankshaft position sensor (REF) Engine speed (REF signal)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Ignition switch Start signal
Throttle position sensor Throttle position
Throttle position switch Closed throttle position
Heated oxygen sensor 1 (front)Density of oxygen in exhaust gas
(Mixture ratio feedback signal)
Fuel tank temperature sensor Fuel temperature in fuel tank
Vehicle speed sensor Vehicle speed
This system controls flow rate of fuel vapor from the EVAP canis-
ter. The opening of the vapor by-pass passage in the EVAP canis-
ter purge volume control solenoid valve changes to control the flow
rate. The EVAP canister purge volume control solenoid valve
repeats ON/OFF operation according to the signal sent from the
ECM. The opening of the valve varies for optimum engine control.
The optimum value stored in the ECM is determined by consider-
ing various engine conditions. When the engine is operating, the
flow rate of fuel vapor from the EVAP canister is regulated as the
air flow changes.
SEF337U
COMPONENT DESCRIPTIONNBEC0221S02The EVAP canister purge volume control solenoid valve uses a
ON/OFF duty to control the flow rate of fuel vapor from the EVAP
canister. The EVAP canister purge volume control solenoid valve
is moved by ON/OFF pulses from the ECM. The longer the ON
pulse, the greater the amount of fuel vapor that will flow through the
valve.
CONSULT-II Reference Value in Data Monitor
Mode
NBEC0222Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
PURG VOL C/VIEngine: After warming up
IAir conditioner switch ªOFFº
IShift lever: ªNº
INo-loadIdle (Vehicle stopped) 0%
2,000 rpm Ð
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DTC P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
(CIRCUIT)
Description
EC-367

SEF058Y
DTC Confirmation ProcedureNBEC0225NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 10 seconds
before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm battery
voltage is more than 11V at idle.
WITH CONSULT-IINBEC0225S011) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Start engine and let it idle for at least 13 seconds.
4) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-371.
WITH GSTNBEC0225S02Follow the proocedure ªWITH CONSULT-IIº above.
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DTC P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
(CIRCUIT)
DTC Confirmation Procedure
EC-369

Diagnostic ProcedureNBEC0227
1 CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE POWER SUPPLY CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect EVAP canister purge volume control solenoid valve harness connector.
SEF986Y
3. Turn ignition switch ªONº.
4. Check voltage between EVAP canister purge volume control solenoid valve terminal 1 and ground with CONSULT-II or
tester.
SEF988Y
OK or NG
OK©GO TO 3.
NG©GO TO 2.
2 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors M32, F23
IFuse block (J/B) connector M10
I10A fuse
IHarness for open or short between EVAP canister purge volume control solenoid valve and fuse
©Repair harness or connectors.
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DTC P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
(CIRCUIT)
Diagnostic Procedure
EC-371

5 CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
With CONSULT-II
Check air passage continuity of EVAP canister purge volume control solenoid valve under the following conditions.
SEF334X
Without CONSULT-II
Check air passage continuity of EVAP canister purge volume control solenoid valve under the following conditions.
SEF335X
OK or NG
OK©GO TO 6.
NG©Replace EVAP canister purge volume control solenoid valve.
6 CHECK INTERMITTENT INCIDENT
Refer to ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-140.
©INSPECTION END
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DTC P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
(CIRCUIT)
Diagnostic Procedure (Cont'd)
EC-373

Possible CauseNBEC0512IHarness or connectors
(The valve circuit is open or shorted.)
IEVAP canister vent control valve
DTC Confirmation ProcedureNBEC0232NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 10 seconds
before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm battery
voltage is more than 11V at idle.
SEF058Y
WITH CONSULT-IINBEC0232S011) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Start engine and wait at least 8 seconds.
4) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-377.
WITH GSTNBEC0232S02Follow the procedure ªWITH CONSULT-IIº above.
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DTC P0446 EVAPORATIVE EMISSION (EVAP) CANISTER VENT CONTROL
VALVE (CIRCUIT)
Possible Cause
EC-375

Diagnostic ProcedureNBEC0234
1 INSPECTION START
1. Do you have CONSULT-II?
YesorNo
Ye s©GO TO 2.
No©GO TO 3.
2 CHECK EVAP CANISTER VENT CONTROL VALVE CIRCUIT
With CONSULT-II
1. Turn ignition switch ªOFFº and then turn ªONº.
2. Select ªVENT CONTROL/Vº in ªACTIVE TESTº mode with CONSULT-II.
3. Touch ªON/OFFº on CONSULT-II screen.
SEF989Y
4. Check for operating sound of the valve.
Clicking noise should be heard.
OK or NG
OK©GO TO 7.
NG©GO TO 3.
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DTC P0446 EVAPORATIVE EMISSION (EVAP) CANISTER VENT CONTROL
VALVE (CIRCUIT)
Diagnostic Procedure
EC-377

6 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors B101, B43
IHarness connectors B1, M2 and M94, F27
IHarness for open or short between EVAP canister vent control valve and ECM
©Repair open circuit or short to ground or short to power in harness or connectors.
7 CHECK RUBBER TUBE FOR CLOGGING
1. Disconnect rubber tube connected to EVAP canister vent control valve.
2. Check the rubber tube for clogging.
OK or NG
OK©GO TO 8.
NG©Clean the rubber tube using an air blower.
8 CHECK EVAP CANISTER VENT CONTROL VALVE-I
1. Remove EVAP canister vent control valve from EVAP canister.
2. Check portionBof EVAP canister vent control valve for being rusted.
SEF337X
OK or NG
OK©GO TO 9.
NG©Replace EVAP canister vent control valve.
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DTC P0446 EVAPORATIVE EMISSION (EVAP) CANISTER VENT CONTROL
VALVE (CIRCUIT)
Diagnostic Procedure (Cont'd)
EC-379

SEF053V
SEF954S
Component DescriptionNBEC0235The EVAP control system pressure sensor detects pressure in the
purge line. The sensor output voltage to the ECM increases as
pressure increases. The EVAP control system pressure sensor is
not used to control the engine system. It is used only for on board
diagnosis.
CONSULT-II Reference Value in Data Monitor
Mode
NBEC0236Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
EVAP SYS PRESIIgnition switch: ON Approx. 3.4V
ECM Terminals and Reference ValueNBEC0668Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
58 B/P Sensors' ground[Engine is running]
IWarm-up condition
IIdle speedApproximately 0V
84 L/GEVAP control system
pressure sensor[Ignition switch ªONº]Approximately 3.4V
111 P/B Sensors' power supply[Ignition switch ªONº]Approximately 5V
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DTC P0450 EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM PRESSURE
SENSOR
Component Description
EC-381