Ac system INFINITI QX4 2001 Factory Service Manual

DescriptionNBEC0691SYSTEM DESCRIPTIONNBEC0691S01
Sensor Input signal to ECM function ECM Actuator
Crankshaft positon sensor (POS) Engine speed (POS)
Intake valve
timing con-
trolIntake valve timing control sole-
noid valve Crankshaft position sensor (REF) Engine speed (REF)
Camshaft position sensor Engine speed
Engine coolant temperature sensor Engine coolant temperature
Vehicle speed sensor Vehicle speed
JEF349Z
This mechanism hydraulically controls cam phases continuously with the fixed operating angle of the intake
valve.
The ECM receives signals such as crankshaft position, camshaft position, engine speed, and engine coolant
temperature. Then, the ECM sends ON/OFF pulse duty signals to the camshaft timing control valve depend-
ing on driving status. This makes it possible to control the shut/open timing of the intake valve to increase
engine torque in low/mid speed range and output in high-speed range.
CONSULT-II Reference Value in Data Monitor
Mode
NBEC0692Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
INT/V TIM (B1)
INT/V TIM (B2)IEngine: After warming up
IShift lever ªNº
IQuickly depressed accelerator
pedal
INo-loadIdle 0É CA
2,000 rpm Approximately 12 - 18É CA
INT/V SOL (B1)
INT/V SOL (B2)IEngine: After warming up
IShift lever ªNº
IQuickly depressed accelerator
pedal
INo-loadIdle 0%
2,000 rpm Approximately 40%
DTC P1110 (RIGHT, -B1), P1135 (LEFT, -B2) INTAKE VALVE TIMING CONTROL
Description
EC-446

DescriptionNBEC0523If DTC P1130 is displayed with P1165, first perform trouble diag-
nosis for DTC P1165, EC-493.
SYSTEM DESCRIPTIONNBEC0523S01
Sensor Input Signal to ECMECM func-
tionActuator
Throttle position sensor Throttle position
Swirl control
valve con-
trolSwirl control valve control sole-
noid valve
"Vacuum signal
Swirl control valve actuator
"
Swirl control valve Ignition switch Start signal
Crankshaft position sensor (POS) Engine speed (POS signal)
Crankshaft position sensor (REF) Engine speed (REF signal)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
This system has a swirl control valve in the intake passage of each
cylinder.
While idling and during low engine speed operation, the swirl con-
trol valve closes. Thus the velocity of the air in the intake passage
increases, promoting the vaporization of the fuel and producing a
swirl in the combustion chamber.
Because of this operation, this system tends to increase the burn-
ing speed of the gas mixture, improve fuel consumption, and
increase the stability in running conditions.
Also, except when idling and during low engine speed operation,
this system opens the swirl control valve. In this condition, this
system tends to increase power by improving intake efficiency via
reduction of intake flow resistance, intake flow.
The solenoid valve controls swirl control valve's shut/open condi-
tion. This solenoid valve is operated by the ECM.
Throttle position
sensor (Idle posi-
tion)Engine speedSwirl control valve
control solenoid
valveSwirl control valve
ON Below 3,200 rpm ON Closed
OFFLess than 3,200
rpmON Closed
More than 3,600
rpmOFF Open
When engine coolant temperature is below 10ÉC (50ÉF) and above 55ÉC (131ÉF),
swirl control valve is kept open regardless of above condition.
SEF446Z
DTC P1130 SWIRL CONTROL VALVE CONTROL SOLENOID VALVE
Description
EC-458

Possible CauseNBEC0527MALFUNCTION ANBEC0527S01IHarness or connectors
(The swirl control valve control solenoid valve circuit is open or
shorted.)
ISwirl control valve control solenoid valve
MALFUNCTION BNBEC0527S02IHarness or connector
(The swirl control valve control solenoid valve circuit is open.)
ISwirl control valve control solenoid valve
IIntake system
(Intake air leaks)
IHoses and tubes between intake manifold, vacuum tank and
swirl control valve actuator
ISwirl control valve actuator
ISwirl control valve control vacuum check switch
IMass air flow sensor
ICrankshaft position sensor (REF)
IThrottle position sensor
MALFUNCTION CNBEC0527S03IHarness or connector
(The swirl control valve control solenoid valve circuit is
shorted.)
ISwirl control valve control vacuum check switch
ICrankshaft position sensor (REF)
IThrottle position sensor
IHoses and tubes between air cleaner and swirl control valve
vacuum check switch
ISwirl control valve control solenoid valve
DTC Confirmation ProcedureNBEC0528Perform ªProcedure for malfunction Aº first. If the 1st trip DTC
cannot be confirmed, perform ªProcedure for malfunction Bº.
If the 1st trip DTC is not confirmed on ªProcedure for malfunc-
tion Bº, perform ªProcedure for malfunction Cº.
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.
SEF058Y
PROCEDURE FOR MALFUNCTION ANBEC0528S01With CONSULT-IINBEC0528S01011) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Wait at least 5 seconds.
If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-463.
With GSTNBEC0528S0102Follow the procedure ªWith CONSULT-IIº above.
DTC P1130 SWIRL CONTROL VALVE CONTROL SOLENOID VALVE
Possible Cause
EC-460

PROCEDURE BNBEC0530S02
1 CHECK INTAKE SYSTEM
1. Start engine and let it idle.
2. Check intake air system for air leaks.
OK or NG
OK (With CONSULT-II)©GO TO 2.
OK (Without CONSULT-
II)©GO TO 3.
NG©Repair intake system.
2 CHECK SWIRL CONTROL VALVE CONTROL SOLENOID VALVE CIRCUIT
With CONSULT-II
1. Select ªSWIRL CONT SOL VALVEº in ªACTIVE TESTº mode with CONSULT-II.
2. Touch ªONº and ªOFFº on CONSULT-II screen.
SEF003Z
3. Make sure that clicking sound is heard from the swirl control valve control solenoid valve.
OK or NG
OK©GO TO 6.
NG©GO TO 3.
DTC P1130 SWIRL CONTROL VALVE CONTROL SOLENOID VALVE
Diagnostic Procedure (Cont'd)
EC-466

SEF999Y
Component DescriptionNBEC0532The swirl control valve control vacuum check switch detects
vacuum signal to the swirl control valve, and sends ªONº or ªOFFº
signal to the ECM.
When vacuum is supplied to the valve, the swirl control valve con-
trol vacuum check switch sends ªOFFº signal to the ECM.
The swirl control valve control vacuum check switch is not used to
control the engine system, it is used for on board diagnosis.
SEF446Z
CONSULT-II Reference Value in Data Monitor
Mode
NBEC0533Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
SWL CON VC SWIEngine speed: Idle
IEngine coolant temperature is between 15ÉC (59ÉF) to 50ÉC (122ÉF).OFF
IEngine speed: Idle
IEngine coolant temperature is above 55ÉC (131ÉF).ON
ECM Terminals and Reference ValueNBEC0674Specification 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)
55 W/BSwirl control valve con-
trol vacuum check
switch[Engine is running]
IIdle speed
IEngine coolant temperature is between 15 to
50ÉC (59 to 122ÉF).Approximately 5V
[Engine is running]
IIdle speed
IEngine coolant temperature is above 55ÉC
(122ÉF).0 - 1.0V
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DTC P1165 SWIRL CONTROL VALVE CONTROL VACUUM CHECK SWITCH
Component Description
EC-493

On Board Diagnosis LogicNBEC0576Malfunction is detected when
(Malfunction A)120É signal is not entered to ECM for the first few
seconds during engine cranking,
(Malfunction B)120É signal is not entered to ECM during engine
running,
(Malfunction C)120É signal cycle excessively changes during
engine running.
FAIL-SAFE MODENBEC0576S01When the ECM enters the fail-safe mode, the MIL illuminates.
Detected items Engine operating condition in fail-safe mode
Crankshaft position sensor (REF)
circuitCompression TDC signal (120É signal) is controlled by camshaft position sensor (PHASE)
signal and crankshaft position sensor (POS) signal. Ignition timing will be delayed 0É to 2É.
Possible CauseNBEC0577IHarness or connectors
(The crankshaft position sensor (REF) circuit is open or
shorted.)
ICrankshaft position sensor (REF)
IStarter motor (Refer to SC section.)
IStarting system circuit (Refer to SC section.)
IDead (Weak) battery
DTC Confirmation ProcedureNBEC0578NOTE:
IPerform ªPROCEDURE FOR MALFUNCTION Aº first. If 1st
trip DTC cannot be confirmed, perform ªPROCEDURE
FOR MALFUNCTION B AND Cº.
IIf 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 that bat-
tery voltage is more than 10.5V at idle.
SEF013Y
PROCEDURE FOR MALFUNCTION ANBEC0578S01With CONSULT-IINBEC0578S01011) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Crank engine for at least 2 seconds.
4) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-514.
With GSTNBEC0578S0102Follow the procedure ªWith CONSULT-IIº above.
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DTC P1335 CRANKSHAFT POSITION SENSOR (CKPS) (REF)
On Board Diagnosis Logic
EC-511

On Board Diagnosis LogicNBEC0316This diagnosis detects very small leaks in the EVAP line between
the fuel tank and the EVAP canister purge volume control solenoid
valve using intake manifold vacuum in the same way as conven-
tional EVAP small leak diagnosis.
If the ECM judges a leak equivalent to a very small leak, the very
small leak DTC P1441 will be detected. If the ECM judges a leak
equivalent to a small leak, the EVAP small leak DTC P0440 will be
detected. Correspondingly, if the ECM judges there is no leak, the
diagnosis result is OK.
SEF373Z
Malfunction is detected when EVAP control system has a very
small leak, EVAP control system does not operate properly.
CAUTION:
IUse only a genuine NISSAN fuel filler cap as a replace-
ment. If an incorrect fuel filler cap is used, the MIL may
come on.
IIf the fuel filler cap is not tightened properly, the MIL may
come on.
IUse only a genuine NISSAN rubber tube as a replacement.
Possible CauseNBEC0587IIncorrect fuel tank vacuum relief valve
IIncorrect fuel filler cap used
IFuel filler cap remains open or fails to close.
IForeign matter caught in fuel filler cap.
ILeak is in line between intake manifold and EVAP canister
purge volume control solenoid valve.
IForeign matter caught in EVAP canister vent control valve.
IEVAP canister or fuel tank leaks
IEVAP purge line (pipe and rubber tube) leaks
DTC P1441 EVAP CONTROL SYSTEM (VERY SMALL LEAK)
On Board Diagnosis Logic
EC-526

IEVAP purge line rubber tube bent.
IBlocked or bent rubber tube to EVAP control system pressure
sensor
ILoose or disconnected rubber tube
IEVAP canister vent control valve and the circuit
IEVAP canister purge volume control solenoid valve
IAbsolute pressure sensor
IFuel tank temperature sensor
IO-ring of EVAP canister vent control valve is missing or dam-
aged.
IWater separator
IEVAP canister is saturated with water.
IFuel level sensor and the circuit
IEVAP control system pressure sensor
SEF881X
SEF882X
SEF883X
DTC Confirmation ProcedureNBEC0317CAUTION:
Never remove fuel filler cap during the DTC confirmation pro-
cedure.
NOTE:
IIf DTC P1441 is displayed with P0440, perform TROUBLE
DIAGNOSIS FOR DTC P1441 first.
IIf ªDIAGNOSTIC TROUBLE CODE CONFIRMATION PRO-
CEDUREº has been previously conducted, always turn
ignition switch ªOFFº and wait at least 5 seconds before
conducting the next test.
IAfter repair, make sure that the hoses and clips are
installed properly.
TESTING CONDITION:
IOpen engine hood before conducting following proce-
dure.
IIf any of following condition is met just before the DTC
confirmation procedure, leave the vehicle for more than 1
hour.
a)Fuel filler cap is removed.
b)Refilled or drained the fuel.
c)EVAP component parts is/are removed.
IBefore performing the following procedure, confirm that
battery voltage is more than 11V at idle.
With CONSULT-II
1) Turn ignition switch ªONº and select ªDATA MONITORº mode
with CONSULT-II.
2) Make sure the following conditions are met.
FUEL LEVEL SE: 1.08 - 0.2V
COOLAN TEMP/S: 0 - 32ÉC (32 - 90ÉF)
FUEL T/TMP SE: 0 - 35ÉC (32 - 95ÉF)
INT A/TEMP SE: More than 0ÉC (32ÉF)
If NG, turn ignition switch ªOFFº and leave the vehicle in a cool
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DTC P1441 EVAP CONTROL SYSTEM (VERY SMALL LEAK)
Possible Cause (Cont'd)
EC-527

place or refilling/draining fuel until the output voltage condition
of the ªFUEL LEVEL SEº meets within the range above and
leave the vehicle for more than 1 hour. Then start from step 1).
3) Turn ignition switch ªOFFº and wait at least 5 seconds.
4) Turn ignition switch ªONº.
5) Select ªEVAP VERY/SML LEAK P1441º of ªEVAPORATIVE
SYSTEMº in ªDTC WORK SUPPORTº mode with CONSULT-
II.
Follow the instruction displayed.
6) Make sure that ªOKº is displayed.
If ªNGº is displayed, refer to ªDiagnostic Procedureº, EC-529.
NOTE:
IIf the engine speed cannot be maintained within the range
displayed on CONSULT-II screen, go to ªBasic
inspectionº, EC-101.
IMake sure that EVAP hoses are connected to EVAP canis-
ter purge volume control solenoid valve properly.
OVERALL FUNCTION CHECKNBEC0317S05With GST
Use this procedure to check the overall function of the EVAP very
small leak function. During this check, a 1st trip DTC might not be
confirmed.
SEF462UA
CAUTION:
INever use compressed air, doing so may damage the
EVAP system.
IDo not start engine.
IDo not exceeded 4.12 kPa (0.042 kg/cm
2, 0.6 psi).
1) Attach the EVAP service port adapter securely to the EVAP
service port.
2) Set the pressure pump and a hose.
3) Also set a vacuum gauge via 3-way connector and a hose.
4) Turn ignition switch ªONº.
5) Connect GST and select mode 8.
6) Using mode 8 control the EVAP canister vent control valve
(close) and vacuum cut valve bypass valve (open).
7) Apply pressure and make sure the following conditions are
satisfied.
Pressure to be applied: 2.7 kPa (20 mmHg, 0.79 inHg)
Time to be waited after the pressure drawn in to the EVAP
system and the pressure to be dropped: 60 seconds and
the pressure should not be dropped more than 0.4 kPa (3
mmHg, 0.12 inHg)
If NG, go to diagnostic procedure, EC-529.
NOTE:
For more information, refer to GST instruction manual.
DTC P1441 EVAP CONTROL SYSTEM (VERY SMALL LEAK)
DTC Confirmation Procedure (Cont'd)
EC-528

Diagnostic ProcedureNBEC0643
1 CHECK FUEL FILLER CAP DESIGN
1. Turn ignition switch ªOFFº.
2. Check for genuine NISSAN fuel filler cap design.
SEF915U
OK or NG
OK©GO TO 2.
NG©Replace with genuine NISSAN fuel filler cap.
2 CHECK FUEL FILLER CAP INSTALLATION
Check that the cap is tightened properly by rotating the cap clockwise.
OK or NG
OK©GO TO 3.
NG©IOpen fuel filler cap, then clean cap and fuel filler neck threads using air blower.
IRetighten until ratcheting sound is heard.
3 CHECK FUEL FILLER CAP FUNCTION
Check for air releasing sound while opening the fuel filler cap.
OK or NG
OK©GO TO 5.
NG©GO TO 4.
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DTC P1441 EVAP CONTROL SYSTEM (VERY SMALL LEAK)
Diagnostic Procedure
EC-529