Fuel sensor INFINITI QX56 2008 Factory Service Manual

MWI-18
< FUNCTION DIAGNOSIS >
METER SYSTEM
SHIFT POSITION INDICATOR : Component Parts Location
INFOID:0000000001696375
SHIFT POSITION INDICATOR : Component DescriptionINFOID:0000000001691273
WARNING LAMPS/INDICATOR LAMPS
WARNING LAMPS/INDICATOR LAMPS : System DiagramINFOID:0000000001691274
1. IPDM E/R E122, E124 2. Combination meter M23, M24 3. Fuel level sensor unit and fuel pump
C5 (view with inspection hole cover re-
moved)
4. ECM E16 (view with battery removed) 5. ABS actuator and electric unit (control
unit) E125 6. Oil pressure switch F4
A: Oil pan (upper)
7. A/T assembly F9 8. BCM M18, M19 (view with instrument
lower panel LH removed)
AWNIA0201ZZ
Unit Description
Combination meter Displays the shift position on the information display using shift position signal received from TCM.
TCM Transmits the shift position signal to the combination meter via CAN communication.
JSNIA0449GB
Revision: March 2010 2008 QX56

MWI
METER SYSTEMMWI-19
< FUNCTION DIAGNOSIS >
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WARNING LAMPS/INDICATOR LAMPS : System DescriptionINFOID:0000000001691275
OIL PRESSURE WARNING LAMP
• IPDM E/R reads the ON/OFF signals from the oil pressure switch and transmits the oil pressure switch sig-
nal to the combination meter via BCM with the CAN communication line.
• The combination meter turns the oil pressure warning lamp ON/OFF according to the oil pressure switch sig- nal received via CAN communication.
WARNING LAMPS/INDICATOR LAMPS : Component Parts LocationINFOID:0000000001696376
WARNING LAMPS/INDICATOR LAMPS : Component DescriptionINFOID:0000000001691277
INFORMATION DISPLAY
1. IPDM E/R E122, E124 2. Combination meter M23, M24 3. Fuel level sensor unit and fuel pump
C5 (view with inspection hole cover re-
moved)
4. ECM E16 (view with battery removed) 5. ABS actuator and electric unit (control unit) E1256. Oil pressure switch F4
A: Oil pan (upper)
7. A/T assembly F9 8. BCM M18, M19 (view with instrument
lower panel LH removed)
AWNIA0201ZZ
Unit Description
Combination meter Turns the oil pressure warning lamp ON/OFF according to the oil pressure switch signal received
from BCM by means of communication.
IPDM E/R Reads the ON/OFF signals from the oil pressure switch and transmits the oil pressure switch signal
to the combination meter via BCM with the CAN communication line.
Oil pressure switch Refer to MWI-35, "
Description".
BCM Transmits the oil pressure switch signal received from IPDM E/R via CAN communication to the
combination meter via CAN communication.
Revision: March 2010
2008 QX56

MWI-20
< FUNCTION DIAGNOSIS >
METER SYSTEM
INFORMATION DISPLAY : System Diagram
INFOID:0000000001691278
INFORMATION DISPLAY : System DescriptionINFOID:0000000001691279
FUNCTION
The information display can indicate the following items.
• Intelligent Key operation information
• Maintenance information
• Warning/Indication messages (Door/liftgate/liftgate glass open, low fuel, low washer fluid, parking brake, A/T
oil temp)
DOOR OPEN WARNING
This warning appears when the ignition switch is ON and the front door LH, front door RH, rear door LH, rear
door RH, back door or glass hatch is opened. The BCM receives a door switch signal from the front door
switch LH, front door switch RH, rear door switch LH, rear door switch RH, back door latch and glass hatch
ajar switch. The BCM sends the door switch signal to the combination meter via CAN communication lines.
Then, when the ignition switch is turned ON, the warning message is displayed.
LOW FUEL WARNING
This warning appears when the fuel level in the fuel tank is less than approximately 11.4 (3 US gal, 2.5 Imp
gal). A variable resistor signal is supplied to the combination meter from the fuel level sensor unit to determine
the amount of fuel in the fuel tank.
LOW WINDSHIELD WASHER FLUID WARNING
This warning appears when the windshield washer fluid level is low. When the windshield washer fluid level is
low, the washer level switch provides a ground signal to the combination meter (unified meter control unit).
Once fluid is added, the message will stay on for 30 seconds and then turn off.
PARKING BRAKE INDICATOR
When the parking brake is applied, the parking brake switch provides a ground signal to the combination
meter (unified meter control unit). Then, when the igni tion switch is turned ON and vehicle speed is greater
than 7 km/h (4 MPH), the message is displayed.
Refer to Owner’s Manual for additional information display items.
AWNIA0202GB
Revision: March 2010 2008 QX56

MWI
METER SYSTEMMWI-21
< FUNCTION DIAGNOSIS >
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INFORMATION DISPLAY : Co mponent Parts LocationINFOID:0000000001696377
INFORMATION DISPLAY : Component DescriptionINFOID:0000000001691281
1. IPDM E/R E122, E124 2. Combination meter M23, M24 3. Fuel level sensor unit and fuel pump
C5 (view with inspection hole cover re-
moved)
4. ECM E16 (view with battery removed) 5. ABS actuator and electric unit (control unit) E1256. Oil pressure switch F4
A: Oil pan (upper)
7. A/T assembly F9 8. BCM M18, M19 (view with instrument
lower panel LH removed)
AWNIA0201ZZ
Unit Description
Combination meter Controls the information display according to the signal received from each unit.
Fuel level sensor unit Refer to MWI-33, "
Description".
BCM Transmits signals provided by various units to the combination meter via CAN communication line.
Washer level switch Transmits the washer level signal to the combination meter.
Parking brake switch Refer to MWI-36, "
Description".
Door switch Transmits the door switch signals to BCM.
Back door latch (door ajar switch) Transmits the back door switch signal to BCM.
Glass hatch ajar switch Transmits the glass hatch ajar switch signal to BCM.
TCM Transmits A/T oil temperature signal to the combination meter with CAN communication line.
Revision: March 2010 2008 QX56

MWI
FUEL LEVEL SENSOR SIGNAL CIRCUITMWI-33
< COMPONENT DIAGNOSIS >
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FUEL LEVEL SENSOR SIGNAL CIRCUIT
DescriptionINFOID:0000000001691293
The fuel level sensor unit and fuel pump detects the approx imate fuel level in the fuel tank and transmits the
fuel level signal to the combination meter.
Component Function CheckINFOID:0000000001691294
1.COMBINATION METER INPUT SIGNAL
1. Select “METER/M&A” on CONSULT-III.
2. Using “FUEL METER” of “DATA MONITOR”, comp are the value of DATA MONITOR with fuel gauge
pointer of combination meter.
Does the data monitor value approximately match the fuel gauge indication?
YES >> Inspection End.
NO >> Replace combination meter. Refer to MWI-76, "
Removal and Installation".
Diagnosis ProcedureINFOID:0000000001691295
1.CHECK HARNESS CONNECTOR
1. Turn ignition switch OFF.
2. Check combination meter and fuel level sensor unit terminals (meter-side and harness-side) for poor con- nection.
Is the inspection result normal?
YES >> GO TO 2
NO >> Repair or replace terminals or connectors.
2.CHECK FUEL LEVEL SENSOR UNIT CIRCUIT
1. Disconnect combination meter connector and fuel level sensor unit connector.
2. Check continuity between combination meter harness connector
(B) and fuel level sensor unit and fuel pump harness connector
(A).
3. Check continuity between fuel level sensor unit and fuel pump harness connector (A) and ground.
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair harness or connector.
Fuel gauge pointer Reference value of data monitor [lit.]
Full Approx. 93
3/4 Approx. 73
1/2 Approx. 52
1/4 Approx. 30
Empty Approx. 11
AB
Continuity
Connector Terminal Connector Terminal
C5 2 M24 3 Yes
A GroundContinuity
Connector Terminal
C5 2 No
AWNIA0206ZZ
Revision: March 2010 2008 QX56

MWI-34
< COMPONENT DIAGNOSIS >
FUEL LEVEL SENSOR SIGNAL CIRCUIT
3.CHECK FUEL LEVEL SENSOR UNIT GROUND CIRCUIT
1. Check continuity between combination meter harness connector (B) and fuel level sensor uni t and fuel pump harness connector
(A).
2. Check continuity between fuel level sensor unit and fuel pump harness connector (A) and ground.
Is the inspection result normal?
YES >> GO TO 4
NO >> Repair harness or connector.
4.CHECK INSTALLATION CONDITION
Check fuel level sensor unit installation, and check whether the float arm interferes or binds with any of the
internal components in the fuel tank.
Is the inspection result normal?
YES >> Inspection End.
NO >> Install the fuel level sensor unit properly.
Component InspectionINFOID:0000000001691296
1.REMOVE FUEL LEVEL SENSOR UNIT
Remove the fuel level sensor unit. Refer to FL-7, "
Removal and Installation".
>> GO TO 2
2.CHECK FUEL LEVEL SENSOR UNIT AND FUEL PUMP
Check the resistance between terminals 2 and 5.
*1 and *2: When float arm is in contact with stopper.
Is inspection result normal?
YES >> Inspection End.
NO >> Replace fuel level sensor unit and fuel pump. Refer to FL-7, "
Removal and Installation".
AB Continuity
Connector Terminal Connector Terminal
C5 5 M24 4 Yes
A GroundContinuity
Connector Terminal
C5 5 No
AWNIA0207ZZ
Te r m i n a l Float position
mm (in) Resistance value
(Approx.)
25 *1 Empty
7.5 (0.3)80Ω
*2 Full 218.9 (8.6)6Ω
LKIA0402E
Revision: March 2010 2008 QX56

MWI-42
< ECU DIAGNOSIS >
COMBINATION METER
ECU DIAGNOSIS
COMBINATION METER
Reference ValueINFOID:0000000001691309
TERMINAL LAYOUT
PHYSICAL VALUES
WKIA5724E
Te r m i -nal Wire
color Item Condition
Reference value (V)
(Approx.)
Ignition
switch Operation or condition
3 Y/L Fuel level sensor signal — —Refer to MWI-12, "
FUEL GAUGE : System
Description".
4 B/P Fuel level sensor ground ON —0
6 BR/W Generator ONGenerator voltage low
0
Generator voltage normal Battery voltage
10 L CAN-H —— —
11 P C A N - L —— —
13 P Air bag warning lamp in-
put ONAir bag warning lamp ON
4
Air bag warning lamp OFF 0
15 BR CK SUSP warning lamp
input —CK SUSP warning lamp
ON
0
CK SUSP warning lamp
OFF Battery voltage
20 B Ground —— 0
21 O/L Ignition switch ON or
START ON
— Battery voltage
23 W/L Washer fluid level switch ON Washer fluid level low
0
Washer fluid level normal Battery voltage
24 O/B Seat belt buckle switch
LH ONUnfastened (ON)
0
Fastened (OFF) Battery voltage
25 P/L Seat belt buckle switch
RH ONUnfastened (ON)
0
Fastened (OFF) Battery voltage
31 G Parking brake switch ON Parking brake applied
0
Parking brake released Battery voltage
32 P/B Brake fluid level switch ON Brake fluid level low
0
Brake fluid level normal Battery voltage
33 R/G Stop lamp switch —Brake pedal depressed
Battery voltage
Brake pedal released 0
Revision: March 2010 2008 QX56

MWI-66
< SYMPTOM DIAGNOSIS >
THE FUEL GAUGE POINTER DOES NOT MOVE
SYMPTOM DIAGNOSIS
THE FUEL GAUGE POINTER DOES NOT MOVE
DescriptionINFOID:0000000001691325
Fuel gauge needle will not move from a certain position.
Diagnosis ProcedureINFOID:0000000001691326
1.CHECK COMBINATION METER INPUT SIGNAL
1. Select “METER/M&A” on CONSULT-III.
2. Using “FUEL METER” of “DATA MONITOR”, comp are the monitor value with the fuel gauge reading on
the combination meter. Refer to MWI-33, "
Component Function Check".
Does monitor value match fuel gauge reading?
YES >> GO TO 2
NO >> Replace combination meter. Refer to MWI-76, "
Removal and Installation".
2.CHECK FUEL LEVEL SENSOR SIGNAL CIRCUIT
Check the fuel level sensor signal circuit. Refer to MWI-33, "
DiagnosisProcedure".
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair harness or connector.
3.CHECK FUEL LEVEL SENSOR UNIT
Perform a unit check for the fuel level sensor unit. Refer to MWI-34, "
Component Inspection".
Is the inspection result normal?
YES >> GO TO 4
NO >> Replace fuel level sensor unit. Refer to FL-7, "
Removal and Installation".
4.CHECK FLOAT INTERFERENCE
Check that the float arm does not interfere or bi nd with any of the components in the fuel tank.
Is the inspection result normal?
YES >> Replace combination meter. Refer to MWI-76, "Removal and Installation".
NO >> Repair or replace malfunctioning parts.
Revision: March 2010 2008 QX56

PCS-6
< FUNCTION DIAGNOSIS >[IPDM E/R]
RELAY CONTROL SYSTEM
System Description
INFOID:0000000001696481
IPDM E/R activates the internal cont rol circuit to perform the relay ON-OFF control according to the input sig-
nals from various sensors and the request signals received from control units via CAN communication.
CAUTION:
IPDM E/R integrated relays cannot be removed.
Control relay Input/outputTransmit unitControl partReference
page
Front fog lamp relay Front fog lamp request signal BCM (CAN) Front fog lampsEXL-15
• Headlamp high relay
• Headlamp low relay • High beam request signal
• Low beam request signal
BCM (CAN)• Headlamp high
• Headlamp lowEXL-7
EXL-7
Tail lamp relay
Position light request signal BCM (CAN) •Parking lamps
• License plate lamps
• Tail lamps
• Trailer tow relay
• Illumination systemEXL-18
• Front wiper relay
• Front wiper high relay
Front wiper request signal BCM (CAN)
Front wiper motorWW-4
Rear window defogger re-
lay Rear window defogger re-
quest signal
BCM (CAN)
Rear window defoggerWW-8
A/C relay A/C request signal •BCM (CAN)
•ECM (CAN)
A/C compressor
HAC-20
Starter relay Ignition switch START signal TCM Starter motorSTR-8
Cooling fan relay Cooling fan request signal ECM (CAN) Cooling fan relayEC-36
Heated mirror relay Heate d mirror request signal BCM (CAN) Door mirrors DEF-4
ECM relayECM relay control signal ECM (CAN) ECM relayEC-21
Throttle control motor relay Throttle control motor control
signal ECM (CAN)
Throttle contro
l motor re-
lay EC-28
Fuel pump relay
Fuel pump request signal ECM (CAN) Fuel pumpEC-28
Ignition relay Ignition switch ON signal Ignition switch Ignition relayEC-31
Revision: March 2010 2008 QX56

PG-48
< COMPONENT DIAGNOSIS >
HARNESS
ENGINE CONTROL HARNESS
ALMIA0227GB
D5 F3 B/1 : A/C CompressorF2 F56 B/8 : Transfer terminal cord assembly
D5 F4 GR/1 : Oil pressure switch G1 F57 B/2 : Transfer motor
D2 F5 GR/4 : Air fuel ratio (A/F) sensor 1 (bank2) F2 F58 GR/6 : Transfer control device (actuator, position
switch)
C4 F6 GR/3 : Ignition coil No. 2 (with power
transistor) F2 F59 B/2 : Wait detection switch
Revision: March 2010
2008 QX56