2008 INFINITI QX56 fuel pump

P0420, P0430 THREE WAY CATALYST FUNCTIONEC-217
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
OK or NG
OK >> GO TO 5.
NG >> Follow the
EC-13, "
Basic Inspection".
5.CHECK FUEL INJECTOR
1. Stop engine and then turn ignition switch ON.
2. Check voltage between ECM terminals 21, 22, 23, 40, 41, 42, 44, 63 and ground with CONSULT-III or tester.
Refer to Wiring Diagram for fuel injector, EC-439, "
Wiring Dia-
gram - ENGINE CONTROL SYSTEM -".
OK or NG
OK >> GO TO 6.
NG >> Perform EC-411, "
Diagnosis Procedure".
6.CHECK FUNCTION OF IGNITION COIL-I
CAUTION:
Do the following procedure in the place where ventilation is good without the combustible.
1. Turn ignition switch OFF.
2. Remove fuel pump fuse in IPDM E/R to release fuel pressure.
NOTE:
Do not use CONSULT-III to release fuel pressure, or fuel pres-
sure applies again during the following procedure.
3. Start engine.
4. After engine stalls, crank it two or three times to release all fuel pressure.
5. Turn ignition switch OFF.
6. Remove all ignition coil harness connectors to avoid the electri- cal discharge from the ignition coils.
7. Remove ignition coil and spark plug of the cylinder to be checked.
8. Crank engine for 5 seconds or more to remove combustion gas in the cylinder.
9. Connect spark plug and harness connector to ignition coil.
10. Fix ignition coil using a rope etc. with gap of 13 - 17 mm between the edge of the spark plug and grounded metal portion
as shown in the figure.
11. Crank engine for about 3 seconds, and check whether spark is
generated between the spark plug and the grounded metal por-
tion.
CAUTION:
• Do not approach to the spark plug and the ignition coilwithin 50cm. Be careful not to get an electrical shock
while checking, because the el ectrical discharge voltage
becomes 20kV or more.
• It might cause to damage the ignition coil if the gap of more than 17 mm is taken.
NOTE:
When the gap is less than 13 mm, the spark might be generated even if the coil is malfunctioning.
OK or NG
OK >> GO TO 10.
Items Specifications
Target idle speed 650 ± 50 rpm (in P or N position)
Ignition timing 15 ± 5° BTDC (in P or N position)
Battery voltage should exist.
PBIB1527E
Spark should be generated.
BBIA0380E
PBIB2325E
Revision: March 2010 2008 QX56

EC-226
< COMPONENT DIAGNOSIS >[VK56DE]
P0442 EVAP CONTROL SYSTEM
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.
4.CHECK FUEL TANK VACUUM RELIEF VALVE
Refer to EC-272, "
Component Inspection" .
OK or NG
OK >> GO TO 5.
NG >> Replace fuel filler cap with a genuine one.
5.INSTALL THE PRESSURE PUMP
To locate the EVAP leak, install EVAP service port adapter and pres-
sure pump to EVAP service port securely.
NOTE:
Improper installation of the EV AP service port adapter to the
EVAP service port may cause leaking.
With CONSULT-III>>GO TO 6.
Without CONSULT-III>>GO TO 7.
6.CHECK FOR EVAP LEAK
With CONSULT-III
1. Turn ignition switch ON.
2. Select “EVAP SYSTEM CLOSE” of “WORK SUPPORT” mode with CONSULT-III.
3. Touch “START” and apply pressure into the EVAP line until the pressure indicator reaches the middle of
the bar graph.
CAUTION:
• Never use compressed air or a high pressure pump.
• Do not exceed 4.12 kPa (0.042 kg/cm
2 , 0.6 psi) of pressure in the system.
BBIA0366E
SEF916U
Revision: March 2010 2008 QX56

P0455 EVAP CONTROL SYSTEMEC-261
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
OK or NG
OK >> GO TO 3.
NG >> 1. Open fuel filler cap, then clean cap and fuel filler neck threads using air blower.
2. Retighten 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.
4.CHECK FUEL TANK VACUUM RELIEF VALVE
Refer to EC-272, "
Component Inspection".
OK or NG
OK >> GO TO 5.
NG >> Replace fuel filler cap with a genuine one.
5.CHECK EVAP PURGE LINE
Check EVAP purge line (pipe, rubber tube, fuel tank and EVAP canister) for cracks, improper connection or
disconnection.
Refer to EC-37, "
Description".
OK or NG
OK >> GO TO 6.
NG >> Repair or reconnect the hose.
6.CLEAN EVAP PURGE LINE
Clean EVAP purge line (pipe and rubber tube) using air blower.
>> GO TO 7.
7.CHECK EVAP CANISTER VENT CONTROL VALVE
Check the following.
• EVAP canister vent control valve is installed properly. Refer to EC-498, "
Removal and Installation".
• EVAP canister vent control valve.
Refer to EC-241, "
Component Inspection".
OK or NG
OK >> GO TO 8.
NG >> Repair or replace EVAP canister vent control valve and O-ring.
8.INSTALL THE PRESSURE PUMP
To locate the EVAP leak, install EVAP service port adapter and pres-
sure pump to EVAP service port securely.
NOTE:
Improper installation of the EV AP service port adapter to the
EVAP service port may cause leaking.
BBIA0366E
Revision: March 2010 2008 QX56

EC-268
< COMPONENT DIAGNOSIS >[VK56DE]
P0456 EVAP CONTROL SYSTEM
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 ON.
5. Connect GST and select Service $08.
6. Using Service $08, control the EV
AP canister vent control valve
(close).
7. Apply pressure and make sure the following conditions are sat- isfied.
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 EC-268, "
Diagnosis Procedure" .
If OK, go to next step.
8. Disconnect GST.
9. Start engine and warm it up to normal operating temperature.
10. Turn ignition switch OFF and wait at least 10 seconds.
11. Restart engine and let it idle for 90 seconds.
12. Keep engine speed at 2,000 rpm for 30 seconds.
13. Turn ignition switch OFF. NOTE:
For more information, refer to GST Instruction Manual.
Diagnosis ProcedureINFOID:0000000001351636
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 proper ly by rotating the cap clockwise.
OK or NG
OK >> GO TO 3.
NG >> 1. Open fuel filler cap, then clean cap and fuel filler neck threads using air blower.
2. Retighten 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.
4.CHECK FUEL TANK VACUUM RELIEF VALVE
Refer to EC-272, "
Component Inspection" .
OK or NG
OK >> GO TO 5.
NG >> Replace fuel filler cap with a genuine one.
SEF462UI
SEF915U
Revision: March 2010 2008 QX56

EC-276
< COMPONENT DIAGNOSIS >[VK56DE]
P0461 FUEL LEVEL SENSOR
P0461 FUEL LEVEL SENSOR
Component DescriptionINFOID:0000000001351644
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 Diagn
osis LogicINFOID:0000000001351645
NOTE:
•If DTC P0461 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-87
.
• If DTC P0461 is displayed with DTC U1010, first pe rform the trouble diagnosis for DTC U1010. Refer
to EC-88
.
Driving long distances naturally affect fuel gauge level.
This diagnosis detects the fuel gauge malfunction of the gauge not moving even after a long distance has
been driven.
Overall Function CheckINFOID:0000000001351646
Use this procedure to check the overall function of the fuel level sensor function. During this check, a 1st trip
DTC might not be confirmed.
WARNING:
When performing following proced ure, be sure to observe the handling of the fuel. Refer to FL-11,
"Removal and Installation".
TESTING CONDITION:
Before starting overall function check, preparation of draining fuel and refi lling fuel is required.
WITH CONSULT-III
NOTE:
Start from step 10, if it is possible to confirm that the fuel cannot be drained by 30 (7-7/8 US gal, 6-5/
8 Imp gal) in advance.
1. Prepare a fuel container and a spare hose.
2. Release fuel pressure from fuel line, refer to EC-494, "
Fuel Pressure Check".
3. Remove the fuel feed hose on the fuel level sensor unit.
4. Connect a spare fuel hose where the fuel feed hose was removed.
5. Turn ignition switch OFF and wait at least 10 seconds then turn ON.
6. Select “FUEL LEVEL SE” in “DAT A MONITOR” mode with CONSULT-III.
7. Check “FUEL LEVEL SE” output voltage and note it.
8. Select “FUEL PUMP” in “ACTIVE TEST” mode with CONSULT-III.
9. Touch “ON” and drain fuel approximately 30 (7-7/8 US gal, 6-5/8 Imp gal) and stop it.
10. Check “FUEL LEVEL SE” output voltage and note it.
11. Fill fuel into the fuel tank for 30 (7-7/8 US gal, 6-5/8 Imp gal).
BBIA0402E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0461
0461 Fuel level sensor circuit
range/performance The output signal of the fuel level sensor does
not change within the specified range even
though the vehicle has been driven a long dis-
tance. • 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
Revision: March 2010 2008 QX56

EC-402
< COMPONENT DIAGNOSIS >[VK56DE]
FUEL PUMP
FUEL PUMP
DescriptionINFOID:0000000001365881
SYSTEM DESCRIPTION
*: ECM determines the start signal status by the signals of engine speed and battery voltage.
The ECM activates the fuel pump for several seconds after the ignition switch is turned ON to improve engine
startability. If the ECM receives a engine speed signal
from the camshaft position sensor (PHASE), it knows
that the engine is rotating, and causes the pump to operate. If the engine speed signal is not received when
the ignition switch is ON, the engine stalls. The EC M stops pump operation and prevents battery discharging,
thereby improving safety. The ECM does not directly drive the fuel pump. It controls the ON/OFF fuel pump
relay, which in turn controls the fuel pump.
COMPONENT DESCRIPTION
A turbine type design fuel pump is used in the fuel tank.
Diagnosis ProcedureINFOID:0000000001365884
1.CHECK OVERALL FUNCTION
1. Turn ignition switch ON.
2. Pinch fuel feed hose with two fingers.
OK or NG
OK >> INSPECTION END
NG >> GO TO 2.
2.CHECK FUEL PUMP POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Turn ignition switch ON.
Sensor Input signal to ECMECM FunctionActuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE) Engine speed*
Fuel pump control Fuel pump relay
Battery Battery voltage*
Condition Fuel pump operation
Ignition switch is turned to ON. Operates for 1 second.
Engine running and cranking Operates.
When engine is stopped Stops in 1.5 seconds.
Except as shown above Stops.
BBIA0402E
Fuel pressure pulsation should be felt on the fuel feed
hose for 1 second after igniti on switch is turned ON.
BBIA0357E
Revision: March 2010 2008 QX56

FUEL PUMPEC-403
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
4. Check voltage between ECM terminal 113 and ground with
CONSULT-IIl or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 3.
3.CHECK FUEL PUMP POWER SUPPLY CIRCUIT-II
Check voltage between IPDM E/R terminal 46 and ground with
CONSULT-IIl or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 13.
4.DETECT MALFUNCTIONING PART
Check harness for open or short between IPDM E/R and ECM.
>> Repair harness or connectors.
5.CHECK CONDENSER-2 POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.
3. Disconnect condenser-2 harness connector.
4. Turn ignition switch ON.
5. Check voltage between condenser-2 terminal 1 and ground with CONSULT-IIl or tester.
6. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> GO TO 6.
6.CHECK 15A FUSE
1. Turn ignition switch OFF. Voltage: Battery voltage
PBIB1187E
Voltage: Battery voltage
PBIB2656E
BBIA0388E
Voltage: Battery voltage should exist for 1 sec-
ond after ignition switch is turned ON.
PBIB0624E
Revision: March 2010 2008 QX56

EC-404
< COMPONENT DIAGNOSIS >[VK56DE]
FUEL PUMP
2. Disconnect 15A fuse.
3. Check 15A fuse.
OK or NG
OK >> GO TO 7.
NG >> Replace fuse.
7.CHECK CONDENSER-2 POWER SUPPLY
CIRCUIT-II FOR OPEN AND SHORT
1. Disconnect IPDM E/R harness connector E119.
2. Check harness continuity between IPDM E/R terminal 13 and condenser-2 terminal 1. Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 13.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
8.CHECK CONDENSER-2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between condenser-2
+ terminal 2 and ground.
Refer to Wiring Diagram.
2. Also check harness for short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to power in harness or connectors.
9.CHECK CONDENSER-2
Refer to EC-405, "
Component Inspection".
OK or NG
OK >> GO TO 10.
NG >> Replace condenser-2.
10.CHECK FUEL PUMP POWER SUPPLY AND GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect “fuel level sensor unit and fuel pump” harness con- nector.
3. Disconnect IPDM E/R harness connector E119.
4. Check harness continuity between IPDM E/R terminal 13 and “fuel level sensor unit and fuel pump” terminal 1, “fuel level sen-
sor unit and fuel pump” terminal 3 and ground.
Refer to Wiring Diagram.
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 .DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E41, C1
• Harness for open or short between fuel pump and IPDM E/R
• Harness for open or short between fuel pump and ground Continuity should exist.
Continuity should exist.
Continuity should exist.
BBIA0583E
Revision: March 2010
2008 QX56