engine control system INFINITI FX35 2008 Service Manual

DTC P0441 EVAP CONTROL SYSTEMEC-923
< SERVICE INFORMATION > [VK45DE]
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2.CHECK PURGE FLOW
With CONSULT-III
1. Disconnect vacuum hose connected to EVAP canister purge volume control solenoid valve at EVAP ser-
vice port and install vacuum gauge. For the location of EVAP service port, refer to EC-618, "
Description".
2. Start engine and let it idle.
3. Select “PURG VOL CONT/V” in “A CTIVE TEST” mode with CONSULT-III.
4. Rev engine up to 2,000 rpm.
5. Touch “Qd” and “Qu” on CONSULT-III screen to adjust “PURG VOL CONT/V” opening and check vacuum
existence.
OK or NG
OK >> GO TO 7.
NG >> GO TO 4.
3.CHECK PURGE FLOW
Without CONSULT-III
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 ser-
vice port and install vacuum gauge. For the location of EVAP service port, refer to EC-618, "
Description".
4. Start engine and let it idle.
Do not depress accelerator pedal even slightly.
5. Check vacuum gauge indication before 60 seconds passed after starting engine.
6. Revving engine up to 2,000 rpm after 100 seconds passed after starting engine.
OK or NG
OK >> GO TO 7.
NG >> GO TO 4.
4.CHECK EVAP PURGE LINE
1. Turn ignition switch OFF.
2. Check EVAP purge line for improper connection or disconnection. Refer to EC-618, "
Description".
OK or NG
OK >> GO TO 5.
NG >> Repair it.
5.CHECK EVAP PURGE HOSE AND PURGE PORT
1. Disconnect purge hoses connect ed to EVAP service port A and
EVAP canister purge volume control solenoid valve B.
2. Blow air into each hose and EVAP purge port C.
PURG VOL CONT/V Vacuum
100% Should exist.0% Should not exist.
Vacuum should not exist.
Vacuum should exist.
SEF367U
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EC-924
< SERVICE INFORMATION >[VK45DE]
DTC P0441 EVAP CONTROL SYSTEM
3. Check that air flows freely.
OK or NG
OK (With CONSULT-III)>>GO TO 6.
OK (Without CONSULT-III)>>GO TO 7.
NG >> Repair or clean hoses and/or purge port.
6.CHECK EVAP CANISTER PURGE VO
LUME CONTROL SOLENOID VALVE
With CONSULT-III
1. Start engine.
2. Perform “PURG VOL CONT/V” in “ACTIVE TEST” m ode with CONSULT-III. Check that engine speed var-
ies according to the valve opening.
OK or NG
OK >> GO TO 8.
NG >> GO TO 7.
7.CHECK EVAP CANISTER PURGE VO LUME CONTROL SOLENOID VALVE
Refer to EC-945, "
Component Inspection".
OK or NG
OK >> GO TO 8.
NG >> Replace EVAP canister purge volume control solenoid valve.
8.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR CONNECTOR
1. Disconnect EVAP control system pressure sensor harness connector.
2. Check connectors for water.
OK or NG
OK >> GO TO 9.
NG >> Replace EVAP control system pressure sensor.
9.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR FUNCTION
Refer to DTC P0452 EC-960, "
DTC Confirmation Procedure", P0453 EC-966, "DTC Confirmation Procedure".
OK or NG
OK >> GO TO 10.
NG >> Replace EVAP control system pressure sensor.
10.CHECK RUBBER TUBE FOR CLOGGING
1. Disconnect rubber tube connected to EV AP canister vent control valve.
2. Check the rubber tube for clogging.
OK or NG
OK >> GO TO 11.
NG >> Clean the rubber tube using an air blower.
11 .CHECK EVAP CANISTER VENT CONTROL VALVE
Refer to EC-949, "
Component Inspection".
OK or NG
OK >> GO TO 12.
NG >> Replace EVAP canister vent control valve.
12.CHECK EVAP PURGE LINE
Inspect EVAP purge line (pipe and rubber tube). Check for evidence of leaks.
SEF368U
Water should not exist.
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EC-926
< SERVICE INFORMATION >[VK45DE]
DTC P0442 EVAP CONTROL SYSTEM
DTC P0442 EVAP CONTROL SYSTEM
On Board Diagn
osis LogicINFOID:0000000001326763
This diagnosis detects leaks in the EVAP purge line using engine intake manifold vacuum.
If pressure does not increase, the ECM will check for l eaks in the line between the fuel tank and EVAP canister
purge volume control solenoid valve, under the following “Vacuum test” conditions.
The EVAP canister vent control valve is closed to s hut the EVAP purge line off. The EVAP canister purge vol-
ume control solenoid valve will then be opened to depressurize the EVAP purge line using intake manifold
vacuum. After this occurs, the EVAP canister purge volume control solenoid valve will be closed.
CAUTION:
 Use only a genuine NISSAN fuel filler cap as a replacemen t. If an incorrect fuel filler cap is used, the
MIL may come on.
 If the fuel filler cap is not tigh tened properly, the MIL may come on.
 Use only a genuine NISSAN rubber tube as a replacement.
DTC Confirmation ProcedureINFOID:0000000001326764
NOTE:
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0442
0442 EVAP control system
small leak detected
(negative pressure) EVAP control system has a leak, EVAP
control system does not operate prop-
erly.  Incorrect fuel tank vacuum relief valve
 Incorrect fuel filler cap used
 Fuel filler cap remains open or fails to close.
 Foreign matter caught in fuel filler cap.
 Leak is in line between intake manifold and EVAP
canister purge volume control solenoid valve.
 Foreign matter caught in EVAP canister vent con- trol valve.
 EVAP canister or fuel tank leaks
 EVAP purge line (pipe and rubber tube) leaks
 EVAP purge line rubber tube bent
 Loose or disconnected rubber tube
 EVAP canister vent control valve and the circuit
 EVAP canister purge volume control solenoid valve and the circuit
 Fuel tank temperature sensor
 O-ring of EVAP canister vent control valve is missing or damaged
 EVAP canister is saturated with water
 EVAP control system pressure sensor
 Fuel level sensor and the circuit
 Refueling EVAP vapor cut valve
 ORVR system leaks
PBIB1026E
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DTC P0442 EVAP CONTROL SYSTEMEC-927
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 If DTC Confirmation Procedure has been previously conduc
ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
 Perform “DTC WORK SUPPORT” when the fuel level is between 1/4 and 3/4 full, and vehicle is placed
on flat level surface.
 Always perform test at a temperature of 0 to 30 °C (32 to 86 °F).
WITH CONSULT-III
1. Turn ignition switch ON.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-III.
4. Make sure that the following conditions are met.
COOLAN TEMP/S: 0 - 70 °C (32 - 158 °F)
INT/A TEMP SE: 0 - 30 °C (32 - 86 °F)
5. Select “EVAP SML LEAK P0442/P1442” of “EVAPORA TIVE SYSTEM” in “DTC WORK SUPPORT” mode
with CONSULT-III.
Follow the instruction displayed.
NOTE:
If the engine speed cannot be maintained within the range displayed on the CONSULT-III screen, go to
EC-658, "
Basic Inspection".
6. Make sure that “OK” is displayed. If “NG” is displayed, refer to EC-927, "
Diagnosis Procedure".
NOTE:
Make sure that EVAP hoses are connected to EVAP canister purge volume control solenoid valve
properly.
WITH GST
NOTE:
Be sure to read the explanation of EC-633, "
Emission-related Diagnostic Information" before driving vehicle.
1. Start engine.
2. Drive vehicle according to EC-633, "
Emission-related Diagnostic Information".
3. Stop vehicle.
4. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
5. Select “Service $07” with GST.  If P0442 is displayed on the screen, go to EC-927, "
Diagnosis Procedure".
 If P0441 is displayed on the screen, go to EC-922, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000001326765
1.CHECK FUEL FILLER CAP DESIGN
1. Turn ignition switch OFF.
2. Check for genuine NISSAN fuel filler cap design.
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.
SEF915U
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EC-930
< SERVICE INFORMATION >[VK45DE]
DTC P0442 EVAP CONTROL SYSTEM
2. Does water drain from the EVAP canister?
Ye s o r N o
Yes >> GO TO 10.
No (With CONSULT-III)>>GO TO 12.
No (Without CONSULT-III)>>GO TO 13.
10.CHECK EVAP CANISTER
Weigh the EVAP canister with the EV AP canister vent control valve and EVAP control system pressure sensor
attached.
The weight should be less than 2.1 kg (4.6 lb).
OK or NG
OK (With CONSULT-III)>>GO TO 12.
OK (Without CONSULT-III)>>GO TO 13.
NG >> GO TO 11.
11 .DETECT MALFUNCTIONING PART
Check the following.
 EVAP canister for damage
 EVAP hose between EVAP canister and vehicle frame for clogging or poor connection
>> Repair hose or replace EVAP canister.
12.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION
With CONSULT-III
1. Disconnect vacuum hose to EVAP canister purge volu me control solenoid valve at EVAP service port.
2. Start engine.
3. Perform “PURG VOL CONT/V ” in “ACTIVE TEST” mode.
4. Touch “Qu” on CONSULT-III screen to increase “PURG VOL CONT/V” opening to 100%.
5. Check vacuum hose for vacuum when revving engine up to 2,000 rpm.
OK or NG
OK >> GO TO 15.
NG >> GO TO 14.
13.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE OPERATION
Without CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Stop engine.
3. Disconnect vacuum hose to EVAP canister purge volu me control solenoid valve at EVAP service port.
4. Start engine and let it idle for at least 80 seconds.
5. Check vacuum hose for vacuum when revving engine up to 2,000 rpm.
OK or NG
OK >> GO TO 16.
NG >> GO TO 14.
14.CHECK VACUUM HOSE
Check vacuum hoses for clogging or disconnection. Refer to EC-684, "
Vacuum Hose Drawing".
OK or NG
OK >> GO TO 15.
NG >> Repair or reconnect the hose.
PBIB1031E
Vacuum should exist.
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DTC P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
EC-933
< SERVICE INFORMATION > [VK45DE]
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DTC P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID
VA LV E
DescriptionINFOID:0000000001326766
SYSTEM DESCRIPTION
*1: ECM determines the start signal status by the signals of engine speed and battery voltage.
*2: This signal is sent to the ECM through CAN communication line.
This system controls flow rate of fuel vapor from
the EVAP canister. The opening of the vapor by-pass pas-
sage in the EVAP canister purge volume control solenoid valve changes to control the flow rate. The EVAP
canister purge volume control solenoid valve repeats ON/O FF operation according to the signal sent from the
ECM. The opening of the valve varies for optimum engi ne control. The optimum value stored in the ECM is
determined by considering various engine conditions. When t he engine is operating, the flow rate of fuel vapor
from the EVAP canister is regulated as the air flow changes.
COMPONENT DESCRIPTION
The EVAP canister purge volume control solenoid valve uses a ON/
OFF duty to control the flow rate of fuel vapor from the EVAP canis-
ter. 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-III Reference Value in Data Monitor ModeINFOID:0000000001326767
Specification data are reference values.
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE) Engine speed*
1
EVAP canister
purge flow controlEVAP canister purge vol-
ume control solenoid valve
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Battery
Battery voltage*
1
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
A/F sensor 1Density of oxygen in exhaust gas
(Mixture ratio feedback signal)
Fuel tank temperature sensor Fuel temperature in fuel tank
Wheel sensor Vehicle speed*
2
SEF337U
MONITOR ITEM CONDITION SPECIFICATION
PURG VOL C/V  Engine: After warming up
 Selector lever: P or N
 Air conditioner switch: OFF
No load Idle 0%
2,000 rpm —
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EC-934
< SERVICE INFORMATION >[VK45DE]
DTC P0443 EVAP CANISTER PURGE VO
LUME CONTROL SOLENOID VALVE
On Board Diagn osis Logic
INFOID:0000000001326768
DTC Confirmation ProcedureINFOID:0000000001326769
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Always perform test at a temperature of 5 °C (41 °F) or more.
WITH CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Select “PURG VOL CN/V P1444” of “EVAPORATIVE SYSTEM” in “DTC WORK SUPPORT” mode with
CONSULT-III.
5. Touch “START”.
6. Start engine and let it idle until “TESTING” on CO NSULT-III changes to “COMPLETED”. (It will take
approximately 10 seconds.)
If “TESTING” is not displayed afte r 5 minutes, retry from step 2.
7. Make sure that “OK” is displayed after touching “ SELF-DIAG RESULTS”. If “NG” is displayed, refer to EC-
936, "Diagnosis Procedure".
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and let it idle for at least 20 seconds.
4. Select “Service $07” with GST.
5. If 1st trip DTC is detected, go to EC-936, "
Diagnosis Procedure".
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0443
0443 EVAP canister purge
volume control solenoid
valve The canister purge flow is detected during the
specified driving conditions, even when EVAP
canister purge volume control solenoid valve is
completely closed.  EVAP control system pressure sensor
 EVAP canister purge volume control so-
lenoid valve
(The valve is stuck open.)
 EVAP canister vent control valve
 EVAP canister
 Hoses (Hoses are connected incorrectly or
clogged.)
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DTC P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
EC-937
< SERVICE INFORMATION > [VK45DE]
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4. Check voltage between EVAP canister purge volume control
solenoid valve terminal 1 and ground with CONSULT-III or
tester.
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors E211, M41
 Harness connectors M82, F102
 IPDM E/R harness connector E7
 Harness for open or short between EVAP canister purge volume control solenoid valve and IPDM E/R
 Harness for open or short between EVAP canister purge volume control solenoid valve and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.
3.CHECK EVAP CANISTER PURGE VOLUME CONTRO L SOLENOID VALVE OUTPUT SIGNAL CIRCUIT
FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 45 and EVAP canister purge volume control solenoid
valve terminal 2. Refer to Wiring Diagram.
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.
4.CHECK EVAP CONTRO L SYSTEM PRESSURE SENSOR CONNECTOR
1. Disconnect EVAP control system pressure sensor harness connector.
2. Check connectors for water.
OK or NG
OK >> GO TO 5.
NG >> Replace EVAP control system pressure sensor.
5.CHECK EVAP CONTROL SYS TEM PRESSURE SENSOR
Refer to EC-965, "
Component Inspection".
OK or NG
OK (With CONSULT-III)>>GO TO 6.
OK (Without CONSULT-III)>>GO TO 7.
NG >> Replace EVAP control system pressure sensor.
6.CHECK EVAP CANISTER PURGE VO LUME CONTROL SOLENOID VALVE
With CONSULT-III
1. Turn ignition switch OFF.
2. Reconnect harness connectors disconnected.
3. Start engine.
4. Perform “PURG VOL CONT/V” in “ACTIVE TEST” mode with CONSULT-III. Check that engine speed var-
ies according to the valve opening. Voltage: Battery voltage
PBIB0148E
Continuity should exist.
Water should not exist.
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EC-940
< SERVICE INFORMATION >[VK45DE]
DTC P0444, P0445 EVAP CANISTER
PURGE VOLUME CONTROL SOLENOID
VALVE
DTC P0444, P0445 EVAP CANISTER PURGE VOLUME CONTROL SOLE-
NOID VALVE
DescriptionINFOID:0000000001326774
SYSTEM DESCRIPTION
*1: ECM determines the start signal status by the signals of engine speed and battery voltage.
*2: This signal is sent to the ECM through CAN communication line.
This system controls flow rate of fuel vapor from the EVAP canister. The opening of the vapor by-pass pas-
sage in the EVAP canister purge volume control sol enoid valve changes to control the flow rate. The EVAP
canister purge volume control solenoid valve repeats ON/O FF operation according to the signal sent from the
ECM. The opening of the valve varies for optimum engi ne control. The optimum value stored in the ECM is
determined by considering various engine conditions. When t he engine is operating, the flow rate of fuel vapor
from the EVAP canister is r egulated as the air flow changes.
COMPONENT DESCRIPTION
The EVAP canister purge volume control solenoid valve uses a ON/
OFF duty to control the flow rate of fuel vapor from the EVAP canis-
ter. 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-III Reference Value in Data Monitor ModeINFOID:0000000001326775
Specification data are reference values.
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE) Engine speed*
1
EVAP canister
purge flow controlEVAP canister purge vol-
ume control solenoid valve
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Battery
Battery voltage*
1
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
A/F sensor 1Density of oxygen in exhaust gas
(Mixture ratio fe
edback signal)
Fuel tank temperature sensor Fuel temperature in fuel tank
Wheel sensor Vehicle speed*
2
SEF337U
MONITOR ITEM CONDITION SPECIFICATION
PURG VOL C/V  Engine: After warming up
 Selector lever: P or N
 Air conditioner switch: OFF
No load Idle 0%
2,000 rpm —
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EC-946
< SERVICE INFORMATION >[VK45DE]
DTC P0447 EVAP CANISTER VENT CONTROL VALVE
DTC P0447 EVAP CANISTER VENT CONTROL VALVE
Component DescriptionINFOID:0000000001326782
The EVAP canister vent control
valve is located on the EVAP canis-
ter and is used to seal the canister vent.
This solenoid valve responds to signals from the ECM. When the
ECM sends an ON signal, the coil in the solenoid valve is energized.
A plunger will then move to seal the canister vent. The ability to seal
the vent is necessary for the on board diagnosis of other evaporative
emission control system components.
This solenoid valve is used only for diagnosis, and usually remains
opened.
When the vent is closed, under normal purge conditions, the evapo-
rative emission control system is depressurized and allows “EVAP
Control System” diagnosis.
CONSULT-III Reference Value in Data Monitor ModeINFOID:0000000001326783
Specification data are reference values.
On Board Diagn osis LogicINFOID:0000000001326784
DTC Confirmation ProcedureINFOID:0000000001326785
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, conf irm battery voltage is more than 11V at idle.
1. Start engine and wait at least 8 seconds.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-948, "
Diagnosis Procedure".
PBIB1263E
PBIB1522E
MONITOR ITEM CONDITION SPECIFICATION
VENT CONT/V  Ignition switch: ON OFF
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0447
0447 EVAP canister vent con-
trol valve circuit open An improper voltage signal is sent to ECM
through EVAP canister vent control valve.  Harness or connectors
(The valve circuit is open or shorted.)
 EVAP canister vent control valve
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