engine INFINITI QX4 2001 Factory Service Manual

ECM Terminals and Reference ValueNBEC0678Specification 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)
1 L/YEVAP canister purge
volume control sole-
noid valve[Engine is running]
IIdle speedBATTERY VOLTAGE
(11 - 14V)
SEF994U
[Engine is running]
IEngine speed is about 2,000 rpm (More than 100
seconds after starting engine).BATTERY VOLTAGE
(11 - 14V)
SEF995U
On Board Diagnosis LogicNBEC0322Malfunction is detected when the canister purge flow is detected
during the specified driving conditions, even when EVAP canister
purge volume control solenoid valve is completely closed.
Possible CauseNBEC0588IEVAP control system pressure sensor
IEVAP canister purge volume control solenoid valve (The valve
is stuck open.)
IEVAP canister vent control valve
IEVAP canister
IHoses
(Hoses are connected incorrectly or clogged.)
DTC P1444 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
ECM Terminals and Reference Value
EC-542

DTC Confirmation ProcedureNBEC0323NOTE:
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:
Always perform test at a temperature of 0ÉC (32ÉF) or more.
SEF205Y
SEF206Y
SEF237Y
WITH CONSULT-IINBEC0323S011) Start engine and warm it up to normal operating temperature.
2) Turn ignition switch ªOFFº and wait at least 10 seconds.
3) Turn ignition switch ªONº.
4) Select ªPURG VOL CN/V P1444º of ªEVAPORATIVE SYS-
TEMº in ªDTC WORK SUPPORTº mode with CONSULT-II.
5) Touch ªSTARTº.
6) Start engine and let it idle until ªTESTINGº on CONSULT-II
changes to ªCOMPLETEDº. (It will take for approximately 10
seconds.)
If ªTESTINGº is not displayed after 5 minutes, retry from
step 2.
7) Make sure that ªOKº is displayed after touching ªSELF-DIAG
RESULTSº. If ªNGº is displayed, refer to ªDiagnostic
Procedureº, EC-545.
WITH GSTNBEC0323S021) Start engine and warm it up to normal operating temperature.
2) Turn ignition switch ªOFFº and wait at least 10 seconds.
3) Start engine and let it idle for at least 20 seconds.
4) Select ªMODE 7º with GST.
5) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-545.
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DTC P1444 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
DTC Confirmation Procedure
EC-543

Diagnostic ProcedureNBEC0325
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 engine ground with CON-
SULT-II or tester.
SEF333X
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.
3 CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OUTPUT SIGNAL CIRCUIT
FOR OPEN AND SHORT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 1 and EVAP canister purge volume control solenoid valve terminal 2.
Refer to Wiring Diagram.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 4.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
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DTC P1444 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
Diagnostic Procedure
EC-545

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

Possible CauseNBEC0589IEVAP canister vent control valve
IEVAP control system pressure sensor and the circuit
IBlocked rubber tube to EVAP canister vent control valve
IWater separator
IEVAP canister is saturated with water.
SEF201Y
DTC Confirmation ProcedureNBEC0330CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 10 seconds
before conducting the next test.
WITH CONSULT-IINBEC0330S011) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Start engine.
4) Drive vehicle at a speed of approximately 80 km/h (50 MPH)
for a maximum of 15 minutes.
NOTE:
If a malfunction exists, NG result may be displayed quicker.
5) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-556.
WITH GSTNBEC0330S02Follow the procedure ªWITH CONSULT-IIº above.
DTC P1446 EVAPORATIVE EMISSION (EVAP) CANISTER VENT CONTROL
VALVE (CLOSE)
Possible Cause
EC-554

IEVAP canister vent control valve
SEF207Y
SEF208Y
SEF238Y
DTC Confirmation ProcedureNBEC0335CAUTION:
Always drive vehicle at a safe speed.
NOTE:
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:
Always perform test at a temperature of 5ÉC (41ÉF) or more.
WITH CONSULT-IINBEC0335S011) Start engine and warm it up to normal operating temperature.
2) Turn ignition switch ªOFFº and wait at least 10 seconds.
3) Start engine and let it idle for at least 70 seconds.
4) Select ªPURG FLOW P1447º of ªEVAPORATIVE SYSTEMº in
ªDTC CONFIRMATIONº mode with CONSULT-II.
5) Touch ªSTARTº.
If ªCOMPLETEDº is displayed, go to step 7.
6) When the following conditions are met, ªTESTINGº will be dis-
played on the CONSULT-II screen. Maintain the conditions
continuously until ªTESTINGº changes to ªCOMPLETEDº. (It
will take at least 35 seconds.)
Selector lever Suitable position
Vehicle speed 32 - 120 km/h (20 - 75 MPH)
ENG SPEED 500 - 3,000 rpm
B/FUEL SCHDL 1.0 - 10 msec
Engine coolant temperature More than 70ÉC (158ÉF)
If ªTESTINGº is not changed for a long time, retry from
step 2.
7) Make sure that ªOKº is displayed after touching ªSELF-DIAG
RESULTSº. If ªNGº is displayed, refer to ªDiagnostic
Procedureº, EC-564.
DTC P1447 EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM PURGE
FLOW MONITORING
Possible Cause (Cont'd)
EC-562

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

Diagnostic Procedure=NBEC0337
1 CHECK EVAP CANISTER
1. Turn ignition switch ªOFFº.
2. Check EVAP canister for cracks.
OK or NG
OK (With CONSULT-II)©GO TO 2.
OK (Without CONSULT-
II)©GO TO 3.
NG©Replace EVAP canister.
2 CHECK PURGE FLOW
With CONSULT-II
1. Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP service port and
install vacuum gauge.
SEF983Y
2. Start engine and let it idle.
3. Select ªPURG VOL CONT/Vº in ªACTIVE TESTº mode with CONSULT-II.
4. Rev engine up to 2,000 rpm.
5. Touch ªQdº and ªQuº on CONSULT-II screen to adjust ªPURG VOL CONT/Vº opening and check vacuum existence.
SEF012Z
OK or NG
OK©GO TO 7.
NG©GO TO 4.
DTC P1447 EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM PURGE
FLOW MONITORING
Diagnostic Procedure
EC-564

3 CHECK PURGE FLOW
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Stop engine.
3. Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP service port and
install vacuum gauge.
SEF983Y
4. Start engine and let it idle for at least 80 seconds.
5. Check vacuum gauge indication when revving engine up to 2,000 rpm.
Vacuum should exist.
6. Release the accelerator pedal fully and let idle.
Vacuum should not exist.
OK or NG
OK©GO TO 7.
NG©GO TO 4.
4 CHECK EVAP PURGE LINE
1. Turn ignition switch ªOFFº.
2. Check EVAP purge line for improper connection or disconnection.
Refer to ªEVAPORATIVE EMISSION LINE DRAWINGº, EC-36.
OK or NG
OK (With CONSULT-II)©GO TO 5.
OK (Without CONSULT-
II)©GO TO 6.
NG©Repair it.
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DTC P1447 EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM PURGE
FLOW MONITORING
Diagnostic Procedure (Cont'd)
EC-565

5 CHECK EVAP PURGE HOSE AND PURGE PORT
1. Disconnect purge hoses connected to EVAP service portAand EVAP canister purge volume control solenoid valveB.
SEF367U
2. Blow air into each hose and EVAP purge portC.
3. Check that air flows freely.
SEF368U
OK or NG
OK©GO TO 6.
NG©Repair or clean hoses and/or purge port.
6 CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
With CONSULT-II
1. Start engine.
2. 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 8.
NG©GO TO 7.
DTC P1447 EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM PURGE
FLOW MONITORING
Diagnostic Procedure (Cont'd)
EC-566