2008 INFINITI QX56 Fuel sensor

FL-16
< DISASSEMBLY AND ASSEMBLY >
FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY
DISASSEMBLY AND ASSEMBLY
FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY
Disassembly and AssemblyINFOID:0000000004900808
Fuel Level Sender Unit
Disassembly
1. Disconnect the harness connectors and the wire connector.
2. Remove the fuel sensor from the pump assembly.
3. Depress the tabs and remove the floater arm assembly.
Assembly
Assembly is the reverse order of disassembly.
AWBIA0680ZZ
1. Harness connector 2. Sending unit module 3. Fuel sensor
4. Floater arm assembly
Revision: March 2010 2008 QX56

GI-16
< HOW TO USE THIS MANUAL >
TERMINOLOGY
TERMINOLOGY
SAE J1930 Terminology ListINFOID:0000000001539196
All emission related terms used in this publication in accordance with SAE J1930 are listed. Accordingly, new
terms, new acronyms/abbreviations and old terms are listed in the following chart.
NEW TERMNEW ACRONYM /
ABBREVIATION OLD TERM
Air cleaner ACL Air cleaner
Barometric pressure BARO ***
Barometric pressure sensor-BCDD BAROS-BCDD BCDD
Camshaft position CMP ***
Camshaft position sensor CMPSCrank angle sensor
Canister *** Canister
Carburetor CARBCarburetor
Charge air cooler CACIntercooler
Closed loop CLClosed loop
Closed throttle position switch CTP switchIdle switch
Clutch pedal position switch CPP switch Clutch switch
Continuous fuel injection system CFI system***
Continuous trap oxidizer system CTOX system ***
Crankshaft position CKP***
Crankshaft position sensor CKPS***
Data link connector DLC***
Data link connector for CONSULT-III DLC for CONSULT-IIIDiagnostic connector for CONSULT-III
Diagnostic test mode DTMDiagnostic mode
Diagnostic test mode selector DTM selectorDiagnostic mode selector
Diagnostic test mode I DTM I Mode I
Diagnostic test mode II DTM IIMode II
Diagnostic trouble code DTCMalfunction code
Direct fuel injection system DFI system ***
Distributor ignition system DI system Ignition timing control
Early fuel evaporation-mixture heater EFE-mixture heater Mixture heater
Early fuel evaporation system EFE system Mixture heater control
Electrically erasable programmable read
only memory EEPROM
***
Electronic ignition system EI systemIgnition timing control
Engine control EC ***
Engine control module ECM ECCS control unit
Engine coolant temperature ECT Engine temperature
Engine coolant temperature sensor ECTS Engine temperature sensor
Engine modification EM ***
Engine speed RPM Engine speed
Erasable programmable read only memory EPROM ***
Evaporative emission canister EVAP canister Canister
Evaporative emission system EVAP system Canister control solenoid valve
Exhaust gas recirculation valve EGR valve EGR valve
Revision: March 2010 2008 QX56

TERMINOLOGYGI-17
< HOW TO USE THIS MANUAL >
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Exhaust gas recirculation control-BPT
valve EGRC-BPT valve
BPT valve
Exhaust gas recirculation control-solenoid
valve EGRC-solenoid valve
EGR control solenoid valve
Exhaust gas recirculation temperature sen-
sor EGRT sensorExhaust gas temperature sensor
EGR temperature sensor
Flash electrically erasable programmable
read only memory FEEPROM
***
Flash erasable programmable read only
memory FEPROM
***
Flexible fuel sensor FFS***
Flexible fuel system FF system***
Fuel pressure regulato r*** Pressure regulator
Fuel pressure regulator control solenoid
valve ***
PRVR control solenoid valve
Fuel trim FT***
Heated Oxygen sensor HO2S Exhaust gas sensor
Idle air control system IAC system Idle speed control
Idle air control valve-air regulato rIACV-air regulator Air regulator
Idle air control valve-auxiliary air control
valve IACV-AAC valve
Auxiliary air control (AAC) valve
Idle air control valve-FICD solenoid valve IACV-FICD solenoid valve FICD solenoid valve
Idle air control valve-idle up control sole-
noid valve IACV-idle up control solenoid valve Idle up control solenoid valve
Idle speed control-FI pot ISC-FI pot FI pot
Idle speed control system ISC system***
Ignition control IC***
Ignition control module ICM***
Indirect fuel injection system IFI system ***
Intake air IA Air
Intake air temperature sensor IAT sensor Air temperature sensor
Knock *** Detonation
Knock sensor KS Detonation sensor
Malfunction indicator lamp MIL Check engine light
Manifold absolute pressure MAP ***
Manifold absolute pressure sensor MAPS ***
Manifold differential pressure MDP ***
Manifold differential pressure sensor MDPS ***
Manifold su rface temperature MST ***
Manifold surface temperature sensor MSTS ***
Manifold vacuum zone MVZ ***
Manifold vacuum zone sensor MVZS***
Mass air flow sensor MAFS Air flow meter
Mixture control solenoid valve MC solenoid valveAir-fuel ratio control solenoid valve
Multiport fuel injection System MFI system Fuel injection control
NEW TERM
NEW ACRONYM /
ABBREVIATION OLD TERM
Revision: March 2010
2008 QX56

GI-18
< HOW TO USE THIS MANUAL >
TERMINOLOGY
Nonvolatile random access memory NVRAM***
On board diagnostic system OBD system Self-diagnosis
Open loop OL Open loop
Oxidation catalyst OC Catalyst
Oxidation catalytic converter system OC system ***
Oxygen sensor O2S Exhaust gas sensor
Park position switch *** Park switch
Transmission range switch *** Park/neutral switch
Inhibitor switch
Neutral position switch
Periodic trap oxidizer system PTOX system ***
Positive crankcase ventilation PCV Positive crankcase ventilation
Positive crankcase ventilation valve PCV valve PCV valve
Powertrain cont rol module PCM ***
Programmable read only memory PROM ***
Pulsed secondary air injection control sole-
noid valve PAIRC solenoid valve
AIV control solenoid valve
Pulsed secondary air injection system PAIR system Air induction valve (AIV) control
Pulsed secondary air injection valve PAIR valve Air induction valve
Random access memory RAM ***
Read only memory ROM ***
Scan tool ST ***
Secondary air injection pump AIR pump***
Secondary air injection system AIR system ***
Sequential multiport fuel injection system SFI system Sequential fuel injection
Service reminder indicator SRI***
Simultaneous multiport fuel injection sys-
tem ***
Simultaneous fuel injection
Smoke puff limiter system SPL system ***
Supercharger SC ***
Supercharger bypass SCB ***
System readiness test SRT ***
Thermal vacuum valve TVVThermal vacuum valve
Three way catalyst TWCCatalyst
Three way catalytic converter system TWC system ***
Three way + oxidation catalyst TWC + OCCatalyst
Three way + oxidation catalytic converter
system TWC + OC system
***
Throttle body TB Throttle chamber
SPI body
Throttle body fuel injection system TBI system Fuel injection control
Throttle position TP Throttle position
Throttle position sensor TPS Throttle sensor
Throttle position switch TP switch Throttle switch
Torque converter clutch solenoid valve TCC solenoid valve Lock-up cancel solenoid
Lock-up solenoid
NEW TERM
NEW ACRONYM /
ABBREVIATION OLD TERM
Revision: March 2010
2008 QX56

PRECAUTIONSGI-27
< PRECAUTION >
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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:0000000001539210
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.
Precaution for Fuel (Unlead ed Premium Gasoline Recommended)INFOID:0000000006211825
INFINITI recommends the use of unleaded premium gasoline with an octane rating of at least 91 AKI (Anti-
Knock Index) number (Research octane number 96).
If unleaded premium gasoline is not available, unleaded regular gasoline with an octane rating of at least 87
AKI number (Research octane number 91) can be us ed, but only under the following precautions:
• have the fuel tank filled only partially with unleaded regular gasoline, and fill up with unleaded premium gas- oline as soon as possible.
• avoid full throttle driving and abrupt acceleration.
However, for maximum vehicle performance, the u se of unleaded premium gasoline is recommended.
CAUTION:
Do not use leaded gasoline. Usin g leaded gasoline will damage the three way catalyst. Using a fuel
other than that specified could adversely affect the emission cont rol devices and systems, and could
also affect the warranty coverage validity.
Multiport Fuel Inje ction System or Engine Control SystemINFOID:0000000001539213
• Before connecting or disconnecting 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:0000000001539214
HOSE REMOVAL AND INSTALLATION
• To prevent damage to rubber hose, do not pry off rubber hose withtapered tool or screwdriver.
SGI787
SMA019D
Revision: March 2010 2008 QX56

LAN
CAN COMMUNICATION SYSTEMLAN-45
< FUNCTION DIAGNOSIS > [CAN]
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Engine speed signal
T RRR R R R R R
Engine status signal TR
Fuel consumption monitor signal TR
RT
ICC steering switch signal TR
Malfunction indicator lamp signal T R
Wide open throttle position signal T R
A/T CHECK indicato r lamp signal T R
A/T fluid temperature sensor signal T R
A/T position indicator lamp signal TR RR
A/T self-diagnosis signal R T
Current gear position signal TR R
Input speed signal R TR
Output shaft revolution signal R TR R
P range signal TR R RR
ICC sensor signal T R
Buzzer output signal TR
TR
ICC OD cancel request signal R RT
ICC operation signal R RT
ICC system display signal TR
System setting signal TRT
RTR
A/C switch/indicator signal TR
RT
A/C switch signal RT R
Blower fan motor switch signal RT
Day time running light request signal TR R
Door lock/unlock status signal TR
Door switch signal R R TR R R
Front fog light request signal TR
Front wiper request signal RT R
High beam request signal TR R
Horn chirp signal TR
Ignition switch signal RTR R
Key fob door unlock signal RT
Key fob ID signal RT
Key switch signal RT
Low beam request signal TR
Position light request signal TR R
Rear window defogger switch signal T RR
Sleep wake up signal RT R R
Theft warning horn request signal TR
Signal name/Connecting unit
ECM
TCM
LASER ICC
ADP AV
BCM
HVAC I-KEY M&A
STRG 4WD
ABS
IPDM-E
Revision: March 2010 2008 QX56

LAN-46
< FUNCTION DIAGNOSIS >[CAN]
CAN COMMUNICATION SYSTEM
NOTE:
CAN data of the air bag diagnosis sensor unit is not us
ed by usual service work, thus it is omitted.
Tire pressure data signal R T
Tire pressure signal R TR
Turn indicator signal TR
Buzzer output signal TR
Door lock/unlock request signal RT
Hazard request signal RT
Hazard warning lamp request signal RT
Ignition knob switch signal RT
KEY warning signal TR
LOCK warning signal TR
Panic alarm request signal RT
Power window open request signal RT
1st position switch signal R T
4th position switch signal R T
Distance to empty signal RT
Fuel level low warning signal RT
Fuel level sensor signal R T
Parking brake switch signal RT
Seat belt buckle switch signal RT
Stop lamp switch signal R T
Tow mode switch signal R T
Vehicle speed signal RRR RRR R T
RRRT
Steering angle sensor signal TR
ABS malfunction signal RT
ABS warning lamp signal RT
Brake pressure sensor signal RT
Brake warning lamp signal RT
SLIP indicator lamp signal RT
TCS malfunction signal RT
VDC malfunction signal RT
VDC OFF indicator lamp signal RRT
VDC operation signal RT
Front wiper stop position signal RT
High beam status signal R T
Hood switch signal RT
Low beam status signal R T
Rear window defogger control signal R RT
Ambient sensor signal RT
Signal name/Connecting unit
ECM
TCM
LASER ICC
ADP
AV
BCM
HVAC I-KEY M&A
STRG 4WDABS
IPDM-E
Revision: March 2010 2008 QX56

ENGINE MAINTENANCEMA-17
< ON-VEHICLE MAINTENANCE >
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2. Fill the radiator and the reservoir tank (to the “MAX”
line), with water. Reinstall the radiator cap and leave
the vented reservoir cap off.
3. Run the engine until it reaches normal operating temperature.
4. Press the engine accelerator two or three times under no-load.
5. Stop the engine and wait until it cools down.
6. Drain the water from the engine cooling system. Refer to CO-11, "
Changing Engine Coolant" .
7. Repeat steps 2 through 6 until clear water begins to drain from the radiator.
Checking Fuel LineINFOID:0000000001606172
Inspect the fuel lines and fuel tank for improper mounting, leaks,
cracks, damage, loose connections, chafing, or deterioration.
As necessary, repair or replace any faulty parts.
Changing Fuel FilterINFOID:0000000001606173
The fuel filter is part of the fuel level sensor unit, fuel filter and fuel pump assembly. Refer to FL-7, "Removal
and Installation" .
WARNING:
Before replacing the fuel filter, release the fuel pressure from the fuel system. Refer to EC-494, "
Fuel
Pressure Check".
Changing Engine Air Cleaner FilterINFOID:0000000001606174
VISCOUS PAPER TYPE
NOTE:
• The viscous paper type filter does not need cleaning between replacement intervals.
• Replace the air filter as necessary for required maintenance.
1. Remove the air duct and resonator assembly.
SMA803A
1. Air cleaner case (upper) 2. Air cleaner filter3. Air cleaner case (lower)
4. Air duct and resonator assembly
WBIA0465E
Revision: March 2010 2008 QX56