2008 INFINITI QX56 fl sensor

MWI
FUEL LEVEL SENSOR SIGNAL CIRCUITMWI-33
< COMPONENT DIAGNOSIS >
C
DE
F
G H
I
J
K L
M B A
O P
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

MWI-74
< PRECAUTION >
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000004894341
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inopera tive, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipmen t on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harn esses can be identified by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Unit or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or electri c power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minu tes before performing any service.
Precaution Necessary for Steering W heel Rotation After Battery Disconnect
INFOID:0000000004894342
NOTE:
• This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
• Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK ″ position.
• Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS, an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be rotated.
4. Perform the necessary repair operation.
Revision: March 2010 2008 QX56

PB-2
< PRECAUTION >
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000004873079
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inopera tive, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipmen t on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harn esses can be identified by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Unit or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or electri c power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minu tes before performing any service.
Precaution Necessary for Steering W heel Rotation After Battery Disconnect
INFOID:0000000004873080
NOTE:
• This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
• Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK ″ position.
• Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS, an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be rotated.
4. Perform the necessary repair operation.
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

PCS-32
< PRECAUTION >[IPDM E/R]
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint Syst
em (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000004857510
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inopera tive, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipmen t on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harn esses can be identified by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Unit or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or electri c power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minu tes before performing any service.
Precaution Necessary for Steering W heel Rotation After Battery Disconnect
INFOID:0000000004857511
NOTE:
• This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
• Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK ″ position.
• Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS, an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be rotated.
4. Perform the necessary repair operation.
Revision: March 2010 2008 QX56