2011 INFINITI QX56 fuel pump

FL-6
< REMOVAL AND INSTALLATION >
FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY
7. Disconnect harness connector (1) and all the fuel tube.
Disconnect quick connector as follows: Hold the sides of connector, push in tabs and pull out fuel feed
tube.
 If quick connector sticks to tube of main fuel level sensor unit, push and pull quick connector several times until they start to
move. Then disconnect them by pulling.
CAUTION:
 Quick connector (1) can be disconnected when the tabs (F) are completely depressed. Never twist it more than
necessary.
 Never use any tools to di sconnected quick connector.
 Keep resin tube (C) away from heat. Be especially careful when welding near the resin tube.
 Prevent acid liquid such as battery electrolyte, etc. from
getting on resin tube.
 Never bend or twist resin tube during installation and dis- connection.
 Never remove the remaining retainer (2) on hard tube (or the equivalent) (A) except when resin tube or retainer is
replaced.
 When resin tube or hard tube (or the equivalent) is replaced, also replace retainer with new one.
2 : Fuel feed tube
3 : Quick connector
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A: Pull
B : Push in tabs
JPBIA0134ZZ
B : Connection (Cross-section)
D : To under floor fuel line
E : To fuel tank
G : Disconnection
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Revision: 2010 May2011 QX56

FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY
FL-7
< REMOVAL AND INSTALLATION >
C
D E
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FL
NP
O
 To keep the connecting portio
n clean and to avoid dam-
age and foreign materials, cover them completely with
plastic bags (A) or something similar.
8. Remove lock ring for fuel level sensor unit, fuel filter and fuel pump assembly with fuel tank lock ring wrench [SST:
KV10119800 (J-45722)] (A) by turning counterclockwise.
9. Remove fuel level sensor unit, fuel filter and fuel pump assem- bly.
CAUTION:
 Never bend float arm during removal.
 Avoid impacts such as fa lling when handling compo-
nents.
INSTALLATION
Note to the following, and install in the reverse order of removal.
 For installation, use a new O-ring.
Quick Connector Connect quick connector as follows:
1. Check the connection for damage or any foreign materials.
2. Align the connector with the tube, then insert the connector straight into the tube until a click sound is
heard.
3. After connecting, check that the connection is secure by following method.  Pull the tube and the connector to check they are securely
connected.
 Visually confirm that the two retainer tabs are connected to the connector.
InspectionINFOID:0000000006289686
INSPECTION AFTER INSTALLATION
Use the following procedure to check for fuel leakage.
1. Turn ignition switch “ON” (with engine stopped), then check connections for leakage by applying fuel pres-
sure to fuel piping.
2. Start engine and let it idle and check there are no fuel leakage at the fuel system connections.
JPBIA0135ZZ
JSBIA0384ZZ
A: Pull
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Revision: 2010 May2011 QX56

FL-8
< REMOVAL AND INSTALLATION >
FUEL TANK
FUEL TANK
Exploded ViewINFOID:0000000006289687
Removal and InstallationINFOID:0000000006289688
WARNING:
Be sure to read “General Precautions” when working on the fuel system. Refer to FL-2, "
General Pre-
cautions".
REMOVAL
CAUTION:
Perform work on level place.
1. Check fuel level on a level ground. If the fuel level is 7/8 of the fuel tank (full or nearly full), draw appropri-
ate amount of fuel from the fuel tank.
 In the event of malfunction in fuel pump, insert a hose measuring 20mm (0.79 in) in diameter into the
filler opening to draw approximately 20 liters fuel.
2. Perform steps 2 to 7 of “REMOVAL” in “ FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY” on fuel level sensor unit, fuel filter and fuel pump assembly. Refer to FL-5, "
Removal and
Installation".
1. Fuel tank side protector 2. Fuel tank side protector 3. Fuel tank front protector
4. Fuel tank protector 5. Fuel tank mounting band 6. Fuel tank
7. Clamp 8. Vent hose 9. Vent hose
10. Fuel filler tube 11. Grommet 12. Fuel filler cap
13. Fuel filler tube protector 14. Clip 15. Clamp
16. Fuel filler hose 17. Fuel filler tube 18. Fuel filler hose
19. Fuel filler tube protector
Refer to GI-4, "
Components" for symbols in the figure.
JSBIA0381GB
Guideline : Draw approximately 20 li ters from a full-tank condition.
Revision: 2010 May2011 QX56

ABBREVIATIONSGI-15
< HOW TO USE THIS MANUAL >
C
DE
F
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E
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H
ABBREVIATION DESCRIPTION E/T Exhaust temperature
EBD Electric brake force distribution EC Engine control
ECL Engine coolant level
ECM Engine control module ECT Engine coolant temperature
ECV Electrical control valve
EEPROM Electrically erasable programmable read only memory EFT Engine fuel temperature
EGR Exhaust gas recirculation
EGRT Exhaust gas recirculation temperature EGT Exhaust gas temperature
EOP Engine oil pressure EP Exhaust pressure
EPR Exhaust pressure regulator EPS Electronically controlled power steering
ESP Electronic stability program system
EVAP canister Evaporative emission canister EXC Exhaust control
ABBREVIATION DESCRIPTION FC Fan control
FCW Forward collision warning FIC Fuel injector controlFP Fuel pump
FR Front
FRP Fuel rail pressure FRT Fuel rail temperature
FTP Fuel tank pressure FTT Fuel tank temperature
ABBREVIATION DESCRIPTION GND GroundGPS Global positioning systemGST Generic scan tool
ABBREVIATION DESCRIPTION HBMC Hydraulic body-motion control systemHDD Hard disk drive
HO2S Heated oxygen sensor HOC Heated oxidation catalyst
Revision: 2010 May2011 QX56

GI-28
< PRECAUTION >
PRECAUTIONS
 Before jacking up the vehicle, apply wheel chocks or other tireblocks to the wheels to prevent t he vehicle from moving. After jack-
ing up the vehicle, support the vehicle weight with safety stands at
the points designated for proper lifting before working on the vehi-
cle.
These operations should be done on a level surface.
 When removing a heavy component such as the engine or tran- saxle/transmission, be careful not to lose your balance and drop
them. Also, do not allow them to strike adjacent parts, especially
the brake tubes and master cylinder.
 Before starting repairs which do not require battery power: Turn off ignition switch.
Disconnect the negative battery terminal.
 If the battery terminals are disconnected, recorded memory of
radio and each control unit is erased.
 To prevent serious burns: Avoid contact with hot metal parts.
Do not remove the radiator cap when the engine is hot.
 Dispose of drained oil or the solvent used for cleaning parts in an appropriate manner.
 Do not attempt to top off the fuel tank after the fuel pump nozzle
shuts off automatically.
Continued refueling may cause fuel overflow, resulting in fuel spray
and possibly a fire.
 Clean all disassembled parts in the designated liquid or solvent prior to inspection or assembly.
 Replace oil seals, gaskets, packings, O-rings, locking washers,
cotter pins, self-locking nuts, etc. with new ones.
 Replace inner and outer races of tapered roller bearings and needle bearings as a set.
 Arrange the disassembled parts in accordance with their assembled locations and sequence.
 Do not touch the terminals of electrical com ponents which use microcomputers (such as ECM).
Static electricity may damage internal electronic components.
 After disconnecting vacuum or air hoses, atta ch a tag to indicate the proper connection.
 Use only the fluids and lubricants specified in this manual.
 Use approved bonding agent, sealants or their equivalents when required.
 Use hand tools, power tools (disassembly only) and recommended special tools where specified for safe and efficient service repairs.
 When repairing the fuel, oil, water, vacuum or exhaust systems, check all affected lines for leakage.
SGI231
SEF289H
SGI233
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Revision: 2010 May2011 QX56

PRECAUTIONSGI-29
< PRECAUTION >
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 Before servicing the vehicle: Protect fenders, upholstery and carpeting with appropriate covers.
Take caution that keys, buckles or buttons do not scratch paint.
WARNING:
To prevent ECM from storing the diagnostic trou ble codes, never carelessly disconnect the harness
connectors which are related to the engine cont rol system and TCM (transmission control module)
system. The connectors should be disconnected only when working according to the WORK FLOW of
TROUBLE DIAGNOSES in EC and TM sections.
Three Way CatalystINFOID:0000000006280871
If a large amount of unburned fuel flows into the catalyst , the catalyst temperature will be excessively high. To
prevent this, follow the instructions.
 Use unleaded gasoline only. Leaded gasoline will seriously damage the three way catalyst.
 When checking for ignition spark or measuring engine compression, make tests quickly and only when nec- essary.
 Do not run engine when the fuel tank level is low, otherwise the engine may misfire, causing damage to the
catalyst.
Do not place the vehicle on flammable material. Keep flammable material off the exhaust pipe and the three
way catalyst.
Multiport Fuel Inje ction System or Engine Control SystemINFOID:0000000006280872
 Before connecting or disconnecti ng any harness connector for the
multiport fuel injection system or ECM:
Turn ignition switch to “OFF” position.
Disconnect negative battery terminal.
Otherwise, there may be damage to ECM.
 Before disconnecting pressurized fuel line from fuel pump to injec- tors, be sure to release fuel pressure.
 Be careful not to jar components such as ECM and mass air flow sensor.
HosesINFOID:0000000006280873
HOSE REMOVAL AND INSTALLATION
 To prevent damage to rubber hose, do not pry off rubber hose withtapered tool or screwdriver.
SGI234
SGI787
SMA019D
Revision: 2010 May2011 QX56

MWI-70
< DTC/CIRCUIT DIAGNOSIS >
FUEL LEVEL SENSOR SIGNAL CIRCUIT
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair harness or connector.
3.CHECK FUEL LEVEL SENSOR GROUND CIRCUIT
Check continuity between fuel level sensor unit harness connector and combination meter harness connector.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Repair harness or connector.
Component InspectionINFOID:0000000006221750
1.REMOVE FUEL LEVEL SENSOR UNIT
Remove the fuel level sensor unit. Refer to FL-5, "
Removal and Installation".
>> GO TO 2.
2.CHECK FUEL LEVEL SENSOR UNIT
Check the resistance between fuel level sensor unit and fuel pump.
*: When float rod is contact with stopper.
Is inspection result OK?
YES >> INSPECTION END
NO >> Replace fuel level sensor unit and fuel pump. Refer to FL-5, "
Removal and Installation".
Combination meter
GroundContinuity
Connector Terminal
M34 34 Not existed
Fuel level sensor unit Combination meter Continuity
Connector Terminal Connector Terminal
C5 5 M34 24 Existed
Te r m i n a l s ConditionResistance (
Ω)
(Approx.) Height [mm (in)]
Fuel level sensor unit
25 Full
* (A)
46.0 282 (11.10)
Empty
* (B) 278.0 29 (1.14)
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Revision: 2010 May2011 QX56

STR-14
< DTC/CIRCUIT DIAGNOSIS >
B TERMINAL CIRCUIT
DTC/CIRCUIT DIAGNOSIS
B TERMINAL CIRCUIT
Diagnosis ProcedureINFOID:0000000006275524
CAUTION:
Perform diagnosis under the condition that engine cannot start by the following procedure.
1. Remove fuel pump fuse.
2. Crank or start the engine (where possi ble) until the fuel pressure is released.
1.CHECK “B” TERMINAL CIRCUIT
1. Turn ignition switch OFF.
2. Check that starter motor “B” terminal connection is clean and tight.
3. Check voltage between starter motor “B” terminal and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Check harness between battery and starter motor for open circuit.
2.CHECK BATTERY CABLE CONNECTION STATUS (VOLTAGE DROP TEST)
1. Shift A/T selector lever to “P” or “N” position.
2. Check voltage between battery positive terminal and starter motor “B” terminal.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Check harness between the battery and the starter motor for poor continuity.
3.CHECK GROUND CIRCUIT STATUS (VOLTAGE DROP TEST)
1. Shift A/T selector lever to “P” or “N” position.
2. Check voltage between starter motor case and battery negative terminal.
Is the inspection result normal?
YES >> “B” terminal circuit is OK. Further inspection is necessary. Refer to STR-11, "Work Flow".
NO >> Check the starter motor case and ground for poor continuity.
(+) (–) Voltage
Starter motor “B” terminal
F57 2 Ground Battery voltage
(+) (–)
ConditionVoltage (V)
(Approx.)
Starter motor “B” terminal
Battery positive terminal F57 2 When the ignition switch
is in START position Less than 0.5
(+) (–) Condition Voltage (V)
(Approx.)
Starter motor case Battery negative terminal When the ignition switch is in START position Less than 0.2
Revision: 2010 May2011 QX56