2009 INFINITI QX56 200

P0442 EVAP CONTROL SYSTEMEC-221
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
NG >> Replace fuel level sensor unit.
24.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "How to Check Terminal"
and GI-38, "Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000003771484
FUEL TANK VACUUM RELIEF VALVE (BUILT INTO FUEL FILLER CAP)
1. Wipe clean valve housing.
2. Check valve opening pressure and vacuum.
3. If out of specificat ion, replace fuel filler cap as an assembly.
CAUTION:
Use only a genuine fuel filler cap as a replacement. If an incor-
rect fuel filler cap is used, the MIL may come on.
SEF445Y
Pressure:
15.3 - 20.0 kPa (0.156 - 0.204 kg/cm2, 2.22 -
2.90 psi)
Vacuum: −6.0 to −3.3 kPa ( −0.061 to −0.034 kg/cm
2,
− 0.87 to −0.48 psi)
SEF943S
Revision: December 20092009 QX56

EC-222
< COMPONENT DIAGNOSIS >[VK56DE]
P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
P0443 EVAP CANISTER PURGE VOLU
ME CONTROL SOLENOID VALVE
DescriptionINFOID:0000000003771485
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.
On Board Diagnosis LogicINFOID:0000000003771486
DTC Confirmation ProcedureINFOID:0000000003771487
NOTE:
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
Air fuel ratio (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
PBIB2057E
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.)
Revision: December 20092009 QX56

P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
EC-223
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
If DTC Confirmation Procedure has been previously conduc
ted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
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 “EVAPORA TIVE 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 “S ELF-DIAG RESULTS”. If “NG” is displayed, refer to EC-
223, "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-223, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771488
1.CHECK EVAP CANISTER PURGE VOLUME CONT ROL SOLENOID VALVE POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect EVAP canister purge volume control solenoid valve harness connector.
3. Turn ignition switch ON.
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.
BBIA0366E
Voltage: Battery voltage
PBIB2245E
Revision: December 20092009 QX56

EC-224
< COMPONENT DIAGNOSIS >[VK56DE]
P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
2.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors E2, F32
 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 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 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 5.
NG >> Replace EVAP control system pressure sensor.
5.CHECK EVAP CONTROL SY STEM PRESSURE SENSOR
Refer to EC-239, "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 all harness connectors disconnected.
3. Start engine.
4. 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-225, "Component Inspection"
.
OK or NG
OK >> GO TO 8.
NG >> Replace EVAP canister purge volume control solenoid valve.
8.CHECK RUBBER TUBE FOR CLOGGING
1. Disconnect rubber tube connected to EV AP canister vent control valve.
Continuity should exist.
Water should not exist.
Revision: December 20092009 QX56

P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
EC-225
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
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G H
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K L
M A
EC
NP
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2. Check the rubber tube for clogging.
OK or NG
OK >> GO TO 9.
NG >> Clean the rubber tube using an air blower.
9.CHECK EVAP CANISTER VENT CONTROL VALVE
Refer to EC-232, "Component Inspection"
.
OK or NG
OK >> GO TO 10.
NG >> Replace EVAP canister vent control valve.
10.CHECK IF EVAP CANISTER SATURATED WITH WATER
1. Remove EVAP canister with EVAP canister vent c ontrol valve and EVAP control system pressure sensor
attached.
2. Check if water will drain from the EVAP canister.
Ye s o r N o
Yes >> GO TO 11.
No >> GO TO 13.
11 .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 2.5 kg (5.5 lb).
OK or NG
OK >> GO TO 13.
NG >> GO TO 12.
12.DETECT MALFUNCTIONING PART
Check the following.
 EVAP canister for damage
 EVAP hose between EVAP canister and vehi cle frame for clogging or poor connection
>> Repair hose or replace EVAP canister.
13.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "How to Check Terminal"
and GI-38, "Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000003771489
EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
With CONSULT-III
BBIA0351E
Revision: December 20092009 QX56

EC-226
< COMPONENT DIAGNOSIS >[VK56DE]
P0443 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
Check air passage continuity of EVAP canister purge volume control
solenoid valve under the following conditions.
Without CONSULT-III
Check air passage continuity of EVAP canister purge volume control
solenoid valve under the following conditions.
Condition
(PURG VOL CONT/V value) Air passage continuity
between A and B
100% Yes 0% No
PBIB2058E
Condition Air passage continuity
between A and B
12V direct current supply between
terminals 1 and 2 Ye s
No supply No
PBIB2059E
Revision: December 20092009 QX56

P0444, P0445 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID
VALVE
EC-227
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
P0444, P0445 EVAP CANISTER PURG
E VOLUME CONTROL SOLENOID
VA LV E
DescriptionINFOID:0000000003771490
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.
On Board Diagnosis LogicINFOID:0000000003771491
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
Air fuel ratio (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
PBIB2057E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0444
0444 EVAP canister purge volume
control solenoid valve circuit
open An excessively low voltage signal is sent
to ECM through the valve  Harness or connectors
(The solenoid valve circuit is open or
shorted.)
 EVAP canister purge volume control so-
lenoid valve
P0445
0445 EVAP canister purge volume
control solenoid valve circuit
shorted An excessively high voltage signal is sent
to ECM through the valve  Harness or connectors
(The solenoid valve circuit is shorted.)
 EVAP canister purge volume control so-
lenoid valve
Revision: December 20092009 QX56

EC-228
< COMPONENT DIAGNOSIS >[VK56DE]
P0444, P0445 EVAP CANISTER P
URGE VOLUME CONTROL SOLENOID
VALVE
DTC Confirmation Procedure
INFOID:0000000003771492
NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing the next step.
1. Turn ignition swich OFF and wait at least 10 seconds.
2. Turn ignition swich ON.
3. Turn ignition swich OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, conf irm battery voltage is more than 11V at idle.
1. Start engine and let it idle for at least 13 seconds.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-228, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003771493
1.CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect EVAP canister purge volume control solenoid valve harness connector.
3. Turn ignition switch ON.
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 E2, F32
 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 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.
BBIA0366E
Voltage: Battery voltage
PBIB2245E
Continuity should exist.
Revision: December 20092009 QX56