2001 INFINITI QX4 air condition

7 CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
With CONSULT-II
1. Turn ignition switch ªOFFº.
2. Reconnect harness connectors disconnected.
3. Start engine.
4. Perform ªPURG VOL CONT/Vº in ªACTIVE TESTº mode with CONSULT-II. Check that engine speed varies according
to the valve opening.
SEF985Y
OK or NG
OK©GO TO 9.
NG©GO TO 8.
8 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 9.
NG©Replace EVAP canister purge volume control solenoid valve.
DTC P1444 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
Diagnostic Procedure (Cont'd)
EC-548

11 CHECK EVAP CANISTER VENT CONTROL VALVE-II
With CONSULT-II
1. Reconnect harness connectors disconnected.
2. Turn ignition switch ªONº.
3. Perform ªVENT CONTROL/Vº in ªACTIVE TESTº mode.
4. Check air passage continuity and operation delay time.
SEF991Y
Without CONSULT-II
Check air passage continuity and operation delay time under the following conditions.
SEF339X
Make sure new O-ring is installed properly.
OK or NG
OK©GO TO 13.
NG©GO TO 12.
12 CHECK EVAP CANISTER VENT CONTROL VALVE-III
1. Clean the air passage (PortionAtoB) of EVAP canister vent control valve using an air blower.
2. Perform procedure 9 again.
OK or NG
OK©GO TO 13.
NG©Replace EVAP canister vent control valve.
DTC P1444 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
Diagnostic Procedure (Cont'd)
EC-550

3 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 4.
NG©Replace EVAP canister vent control valve.
4 CHECK EVAP CANISTER VENT CONTROL VALVE-II
With CONSULT-II
1. Turn ignition switch ON.
2. Perform ªVENT CONTROL/Vº in ªACTIVE TESTº mode.
3. Check air passage continuity and operation delay time.
SEF991Y
Without CONSULT-II
Check air passage continuity and operation delay time under the following conditions.
SEF339X
Make sure new O-ring is installed properly.
OK or NG
OK©GO TO 6.
NG©GO TO 5.
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DTC P1446 EVAPORATIVE EMISSION (EVAP) CANISTER VENT CONTROL
VALVE (CLOSE)
Diagnostic Procedure (Cont'd)
EC-557

System DescriptionNBEC0333NOTE:
If DTC P1447 is displayed with P0510, perform trouble diagnosis for DTC P0510 first. (See EC-431.)
SEF373Z
In this evaporative emission (EVAP) control system, purge flow occurs during non-closed throttle conditions.
Purge volume is related to air intake volume. Under normal purge conditions (non-closed throttle), the EVAP
canister purge volume control solenoid valve is open to admit purge flow. Purge flow exposes the EVAP con-
trol system pressure sensor to intake manifold vacuum.
On Board Diagnosis LogicNBEC0334Under normal conditions (non-closed throttle), sensor output volt-
age indicates if pressure drop and purge flow are adequate. If not,
a fault is determined.
Malfunction is detected when EVAP control system does not oper-
ate properly, EVAP control system has a leak between intake mani-
fold and EVAP control system pressure sensor.
Possible CauseNBEC0590IEVAP canister purge volume control solenoid valve stuck
closed
IEVAP control system pressure sensor and the circuit
ILoose, disconnected or improper connection of rubber tube
IBlocked rubber tube
ICracked EVAP canister
IEVAP canister purge volume control solenoid valve circuit
IClosed throttle position switch
IBlocked purge port
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DTC P1447 EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM PURGE
FLOW MONITORING
System Description
EC-561

SEF355X
Overall Function CheckNBEC0336Use this procedure to check the overall monitoring function of the
EVAP control system purge flow monitoring. During this check, a
1st trip DTC might not be confirmed.
WITH GSTNBEC0336S011) Lift up drive wheels.
2) Start engine (TCS switch ªOFFº) and warm it up to normal
operating temperature.
3) Turn ignition switch ªOFFº, wait at least 10 seconds.
4) Start engine and wait at least 70 seconds.
5) Set voltmeter probes to ECM terminals 84 (EVAP control sys-
tem pressure sensor signal) and ground.
6) Check EVAP control system pressure sensor value at idle
speed and note it.
7) Establish and maintain the following conditions for at least 1
minute.
Air conditioner switch ON
Steering wheel Fully turned
Headlamp switch ON
Rear window defogger switch ON
Engine speed Approx. 3,000 rpm
Gear position Any position other than ªPº, ªNº or ªRº
8) Verify that EVAP control system pressure sensor value stays
0.1V less than the value at idle speed (measured at step 6) for
at least 1 second.
9) If NG, go to ªDiagnostic Procedureº, EC-564.
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DTC P1447 EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM PURGE
FLOW MONITORING
Overall Function Check
EC-563

7 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 8.
NG©Replace EVAP canister purge volume control solenoid valve.
8 CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR HOSE
1. Turn ignition switch ªOFFº.
2. Check disconnection or improper connection of hose connected to EVAP control system pressure sensor.
OK or NG
OK©GO TO 9.
NG©Repair it.
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DTC P1447 EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM PURGE
FLOW MONITORING
Diagnostic Procedure (Cont'd)
EC-567

13 CHECK EVAP CANISTER VENT CONTROL VALVE-II
With CONSULT-II
1. Reconnect harness connectors disconnected.
2. Turn ignition switch ªONº.
3. Perform ªVENT CONTROL/Vº in ªACTIVE TESTº mode.
4. Check air passage continuity and operation delay time.
SEF991Y
Without CONSULT-II
Check air passage continuity and operation delay time under the following conditions.
SEF339X
Make sure new O-ring is installed properly.
OK or NG
OK©GO TO 15.
NG©GO TO 14.
14 CHECK EVAP CANISTER VENT CONTROL VALVE-III
1. Clean the air passage (PortionAtoB) of EVAP canister vent control valve using an air blower.
2. Perform Test No. 13 again.
OK or NG
OK (With CONSULT-II)©GO TO 16.
OK (Without CONSULT-
II)©GO TO 16.
NG©Replace EVAP canister vent control valve.
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DTC P1447 EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM PURGE
FLOW MONITORING
Diagnostic Procedure (Cont'd)
EC-569

SEF013Z
11) Make sure the following.
Condition
VENT CONTROL/VAir passage continuity
betweenAandB
ON No
OFF Yes
If the result is NG, go to ªDiagnostic Procedureº, EC-577.
If the result is OK, go to ªDiagnostic Procedureº for DTC
P0440, EC-355.
AEC783A
Overall Function CheckNBEC0343Use this procedure to check the overall function of the EVAP can-
ister vent control valve circuit. During this check, a DTC might not
be confirmed.
WITH GSTNBEC0343S011) Disconnect hose from water separator.
2) Disconnect EVAP canister vent control valve harness connec-
tor.
3) Verify the following.
Condition Air passage continuity
12V direct current supply between ter-
minals 1 and 2No
No supply Yes
If the result is NG, go to ªDiagnostic Procedureº, EC-577.
If the result is OK, go to ªDiagnostic Procedureº for DTC
P0440, EC-355.
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DTC P1448 EVAPORATIVE EMISSION (EVAP) CANISTER VENT CONTROL
VALVE (OPEN)
DTC Confirmation Procedure (Cont'd)
EC-575