Page 1512 of 3419

DTC P0444, P0445 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID
VALVE
EC-321
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: October 20052005 QX56
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
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.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
45 L/YEVAP canister purge vol-
ume control solenoid valve[Engine is running]
Idle speed
Accelerator pedal: Not depressed even
slightly, after starting engine.BATTERY VOLTAGE
(11 - 14V)
[Engine is running]
Engine speed: About 2,000 rpm (More than
100 seconds after starting engine).11 - 1 4 V
111 W / BECM relay
(Self shut-off)[Engine is running]
[Ignition switch: OFF]
For a few seconds after turning ignition
switch OFF0 - 1.5V
[Ignition switch: OFF]
More than a few seconds after turning igni-
tion switch OFFBATTERY VOLTAGE
(11 - 14V)
11 9
120BR
BRPower supply for ECM[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)
PBIB0050E
PBIB0051E
Page 1513 of 3419

EC-322Revision: October 2005
DTC P0444, P0445 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID
VALVE
2005 QX56
Diagnostic ProcedureUBS00H4W
1. CHECK EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE POWER SUPPLY CIR-
CUIT
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-II 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 CONTROL SOLENOID VALVE OUTPUT SIGNAL CIR-
CUIT 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 (With CONSULT-II)>>GO TO 4.
OK (Without CONSULT-II)>>GO TO 5.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
BBIA0366E
Voltage: Battery voltage
PBIB2245E
Continuity should exist.
Page 1517 of 3419
EC-326Revision: October 2005
DTC P0447 EVAP CANISTER VENT CONTROL VALVE
2005 QX56
DTC Confirmation ProcedureUBS00H52
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm battery voltage is more than 11V at idle.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Start engine and wait at least 8 seconds.
4. If 1st trip DTC is detected, go to EC-328, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
SEF 0 58 Y
Page 1519 of 3419
EC-328Revision: October 2005
DTC P0447 EVAP CANISTER VENT CONTROL VALVE
2005 QX56
Specification 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.
Diagnostic ProcedureUBS00H54
1. INSPECTION START
Do you have CONSULT-II?
Ye s o r N o
Yes >> GO TO 2.
No >> GO TO 3.
2. CHECK EVAP CANISTER VENT CONTROL VALVE CIRCUIT
With CONSULT-II
1. Turn ignition switch OFF and then turn ON.
2. Select “VENT CONTROL/V” in “ACTIVE TEST” mode with CONSULT-II.
3. Touch “ON/OFF” on CONSULT-II screen.
4. Check for operating sound of the valve.
Clicking noise should be heard.
OK or NG
OK >> GO TO 7.
NG >> GO TO 3.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
11 7 L / YEVAP canister vent control
valve[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)
PBIB1679E
Page 1520 of 3419

DTC P0447 EVAP CANISTER VENT CONTROL VALVE
EC-329
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: October 20052005 QX56
3. CHECK EVAP CANISTER VENT CONTROL VALVE POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect EVAP canister vent control valve harness connector.
3. Turn ignition switch ON.
4. Check voltage between EVAP canister vent control valve termi-
nal 1 and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4. DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E41, C1
IPDM E/R harness connector E119
Harness for open or short between EVAP canister vent control valve and IPDM E/R
>> Repair harness or connectors.
5. CHECK EVAP CANISTER VENT CONTROL 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 117 and EVAP canister vent control 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 7.
NG >> GO TO 6.Voltage: Battery voltage
BBIA0443E
PBIB0152E
Continuity should exist.
Page 1549 of 3419

EC-358Revision: October 2005
DTC P0456 EVAP CONTROL SYSTEM
2005 QX56
CAUTION:
Use only a genuine NISSAN fuel filler cap as a replacement. If an incorrect fuel filler cap is used,
the MIL may come on.
If the fuel filler cap is not tightened properly, the MIL may come on.
Use only a genuine NISSAN rubber tube as a replacement.
DTC Confirmation ProcedureUBS00H5U
NOTE:
If DTC P0456 is displayed with P0442, first perform trouble diagnosis for DTC P0456.
After repair, make sure that the hoses and clips are installed properly.
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait
at least 10 seconds before conducting the next test.
TESTING CONDITION:
Open engine hood before conducting following procedure.
If any of following conditions are met just before the DTC confirmation procedure, leave the vehi-
cle for more than 1 hour.
–Fuel filler cap is removed.
–Fuel is refilled or drained.
–EVAP component parts is/are removed.
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
WITH CONSULT-II
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-II.
2. Make sure the following conditions are met.
FUEL LEVEL SE: 0.25 - 1.4V
COOLAN TEMP/S: 0 - 32°C (32 - 90°F)
FUEL T/TMP SE: 0 - 35°C (32 - 95°F)
INT/A TEMP SE: More than 0°C (32°F)
If NG, turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle) or refilling/draining
fuel until the output voltage condition of the “FUEL LEVEL SE” meets within the range above and leave
the vehicle for more than 1 hour. Then start from step 1).
3. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
4. Select “EVAP V/S LEAK P0456/P1456” of “EVAPORATIVE SYSTEM” in “DTC WORK SUPPORT” mode
with CONSULT-II.
Follow the instruction displayed.
5. Make sure that “OK” is displayed.
If “NG” is displayed, refer to EC-360, "
Diagnostic Procedure" .
NOTE:
If the engine speed cannot be maintained within the range displayed on CONSULT-II screen, go
to EC-72, "
Basic Inspection" .
Make sure that EVAP hoses are connected to EVAP canister purge volume control solenoid
valve properly.
PBIB0837E
Page 1561 of 3419

EC-370Revision: October 2005
DTC P0462, P0463 FUEL LEVEL SENSOR CIRCUIT
2005 QX56
DTC P0462, P0463 FUEL LEVEL SENSOR CIRCUITPFP:25060
Component DescriptionUBS00H67
The fuel level sensor is mounted in the fuel level sensor unit. The
sensor detects a fuel level in the fuel tank and transmits a signal to
the combination meter. The combination meter sends the fuel level
sensor signal to the ECM through CAN communication line.
It consists of two parts, one is mechanical float and the other is vari-
able resistor. Fuel level sensor output voltage changes depending on
the movement of the fuel mechanical float.
On Board Diagnosis LogicUBS00H68
NOTE:
If DTC P0462 or P0463 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for
DTC U1000, U1001. Refer to EC-163, "
DTC U1000, U1001 CAN COMMUNICATION LINE" .
This diagnosis indicates the former, to detect open or short circuit malfunction.
DTC Confirmation ProcedureUBS00H69
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at ignition
switch ON.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Wait at least 5 seconds.
4. If 1st trip DTC is detected, go to EC-371, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
BBIA0402E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0462
0462Fuel level sensor circuit
low inputAn excessively low voltage from the sensor is
sent to ECM.
Harness or connectors
(The CAN communication line is open or
shorted)
Harness or connectors
(The sensor circuit is open or shorted)
Combination meter
Fuel level sensor P0463
0463Fuel level sensor circuit
high inputAn excessively high voltage from the sensor is
sent to ECM.
SEF 1 95 Y
Page 1565 of 3419

EC-374Revision: October 2005
DTC P0506 ISC SYSTEM
2005 QX56
DTC P0506 ISC SYSTEMPFP:23781
DescriptionUBS00H6H
NOTE:
If DTC P0506 is displayed with other DTC, first perform the trouble diagnosis for the other DTC.
The ECM controls the engine idle speed to a specified level through the fine adjustment of the air, which is let
into the intake manifold, by operating the electric throttle control actuator. The operating of the throttle valve is
varied to allow for optimum control of the engine idling speed. The crankshaft position sensor (POS) detects
the actual engine speed and sends a signal to the ECM.
The ECM controls the electric throttle control actuator so that the engine speed coincides with the target value
memorized in the ECM. The target engine speed is the lowest speed at which the engine can operate steadily.
The optimum value stored in the ECM is determined by taking into consideration various engine conditions,
such as during warming up, deceleration, and engine load (air conditioner, power steering and cooling fan
operation, etc.).
On Board Diagnosis LogicUBS00H6I
DTC Confirmation ProcedureUBS00H6J
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait
at least 10 seconds before conducting the next test.
If the target idle speed is out of the specified value, perform EC-91, "Idle Air Volume Learning" ,
before conducting DTC Confirmation Procedure. For the target idle speed, refer to the EC-669,
"SERVICE DATA AND SPECIFICATIONS (SDS)" .
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
Always perform the test at a temperature above −10°C (14°F).
WITH CONSULT-II
1. Open engine hood.
2. Start engine and warm it up to normal operating temperature.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON again and select “DATA MONITOR”
mode with CONSULT-II.
5. Start engine and run it for at least 1 minute at idle speed.
6. If 1st trip DTC is detected, go to EC-375, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0506
0506Idle speed control system
RPM lower than expectedThe idle speed is less than the target idle
speed by 100 rpm or more.
Electric throttle control actuator
Intake air leak
SEF 1 74 Y