sensor INFINITI QX56 2008 Factory Service Manual

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

FUEL PUMPEC-405
< COMPONENT DIAGNOSIS > [VK56DE]
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>> Repair open circuit or short to ground or short to power in harness or connectors.
12.CHECK FUEL PUMP
Refer to EC-405, "
Component Inspection".
OK or NG
OK >> GO TO 13.
NG >> Replace “fuel level sensor unit and fuel pump”.
13.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
OK or NG
OK >> Replace IPDM E/R.
NG >> Repair or replace harness or connectors.
Component InspectionINFOID:0000000001365885
FUEL PUMP
1. Disconnect “fuel level sensor unit and fuel pump” harness connector.
2. Check resistance between fuel level sensor unit and fuel pump terminals 1 and 3.
CONDENSER-2
1. Turn ignition switch OFF.
2. Disconnect condenser-2 harness connector.
3. Check resistance between condenser-2 terminals as 1 and 2. Resistance: 0.2 - 5.0
Ω [at 25 °C (77 °F)]
SEC918C
Resistance Above 1 MΩ at 25 °C (77 °F)
PBIB0794E
Revision: March 2010 2008 QX56

EC-416
< COMPONENT DIAGNOSIS >[VK56DE]
ON BOARD REFUELING VAPOR RECOVERY (ORVR)
ON BOARD REFUELING VAPOR RECOVERY (ORVR)
System DescriptionINFOID:0000000001351317
From the beginning of refueling, the air and vapor insi
de the fuel tank go through refueling EVAP vapor cut
valve and EVAP/ORVR line to the EVAP canister. The vapor is absorbed by the EVAP canister and the air is
released to the atmosphere.
When the refueling has reached the full level of the fuel tank, the refueling EVAP vapor cut valve is closed and
refueling is stopped because of auto shut-off. The vapor which was absorbed by the EVAP canister is purged
during driving.
WARNING:
When conducting inspections below, be sure to observe the following:
• Put a “CAUTION: FLAMMABLE” sign in workshop.
• Do not smoke while servicing fuel system. Keep open flames and sparks away from work area.
• Be sure to furnish the workshop with a CO
2 fire extinguisher.
CAUTION:
• Before removing fuel line parts, carry out the following procedures:
- Put drained fuel in an explosion-pr oof container and put lid on securely.
- Release fuel pressure from fuel line. Refer to EC-494, "
Fuel Pressure Check" .
- Disconnect battery ground cable.
• Always replace O-ring when the fu el gauge retainer is removed.
• Do not kink or twist hose and tube when they are installed.
• Do not tighten hose and clamps excessively to avoid damaging hoses.
• After installation, run engine and check for fuel leaks at connection.
• Do not attempt to top off the fuel tank afte r the fuel pump nozzle shuts off automatically.
Continued refueling may cause fuel overflow, r esulting in fuel spray and possibly a fire.
Diagnosis ProcedureINFOID:0000000001351318
SYMPTOM: FUEL ODOR FROM EVAP CANISTER IS STRONG.
1.CHECK EVAP CANISTER
1. Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor attached.
2. Weigh the EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor
attached.
The weight should be l ess than 2.5 kg (5.5 lb).
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
2.CHECK IF EVAP CANISTER SATURATED WITH WATER
PBIB1068E
Revision: March 2010 2008 QX56

ON BOARD REFUELING VAPOR RECOVERY (ORVR)EC-417
< COMPONENT DIAGNOSIS > [VK56DE]
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Does water drain from
the EVAP canister?
Ye s o r N o
Yes >> GO TO 3.
No >> GO TO 5.
3.REPLACE EVAP CANISTER
Replace EVAP canister with a new one.
>> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the EVAP hose between EVAP canister and vehicle frame for clogging or poor connection.
>> Repair or replace EVAP hose.
5.CHECK REFUELING EVAP VAPOR CUT VALVE
Refer to EC-418, "
Component Inspection" .
OK or NG
OK >> INSPECTION END
NG >> Replace refueling EVAP vapor cut valve with fuel tank.
SYMPTOM: CANNOT REFUEL/FUEL ODOR FROM THE FUEL FILLER OPENING IS STRONG
WHILE REFUELING.
1.CHECK EVAP CANISTER
1. Remove EVAP canister with EVAP canister vent c ontrol valve and EVAP control system pressure sensor
attached.
2. Weigh the EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor
attached.
The weight should be l ess than 2.5 kg (5.5 lb).
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
2.CHECK IF EVAP CANISTER SATURATED WITH WATER
Does water drain from the EVAP canister?
Ye s o r N o
Yes >> GO TO 3.
No >> GO TO 5.
3.REPLACE EVAP CANISTER
Replace EVAP canister with a new one.
>> GO TO 4.
BBIA0351E
BBIA0351E
Revision: March 2010 2008 QX56

REFRIGERANT PRESSURE SENSOREC-423
< COMPONENT DIAGNOSIS > [VK56DE]
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REFRIGERANT PRESSURE SENSOR
Component DescriptionINFOID:0000000001365897
The refrigerant pressure sensor is installed at the condenser of the
air conditioner system. The sensor uses an electrostatic volume
pressure transducer to convert refrigerant pressure to voltage. The
voltage signal is sent to ECM, and ECM controls cooling fan system.
Diagnosis ProcedureINFOID:0000000001365899
1.CHECK REFRIGERANT PRESSURE
SENSOR OVERALL FUNCTION
1. Start engine and warm it up to normal operating temperature.
2. Turn A/C switch and blower fan switch ON.
3. Check voltage between ECM terminal 70 and ground with CON- SULT-IIl or tester.
OK or NG
OK >> INSPECTION END
NG >> GO TO 2.
2.CHECK GROUND CONNECTIONS
1. Turn A/C switch and blower fan switch OFF.
2. Turn ignition switch OFF.
3. Loosen and retighten three ground screws on the body.
BBIA0445E
PBIB2657E
Voltage: 1.0 - 4.0V
PBIB1188E
Revision: March 2010 2008 QX56

EC-424
< COMPONENT DIAGNOSIS >[VK56DE]
REFRIGERANT PRESSURE SENSOR
Refer to EC-86, "Ground Inspection".
OK or NG
OK >> GO TO 3.
NG >> Repair or replace ground connections.
3.CHECK REFRIGERANT PRESSURE SENSOR POWER SUPPLY CIRCUIT
1. Disconnect refrigerant pressure sensor harness connector.
2. Turn ignition switch ON.
3. Check voltage between refrigerant pressure sensor terminal 1 and ground with CONSULT-IIl or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E5, F14
• Harness for open or short between ECM and refrigerant pressure sensor
>> Repair harness or connectors.
5.CHECK REFRIGERANT PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between refrigerant pressure sensor terminal 3 and ECM terminal 67. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
BBIA0354E
BBIA0445E
Voltage: Approximately 5V
PBIB0188E
Continuity should exist.
Revision: March 2010 2008 QX56

REFRIGERANT PRESSURE SENSOREC-425
< COMPONENT DIAGNOSIS > [VK56DE]
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6.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E5, F14
• Harness for open or short between ECM and refrigerant pressure sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
7.CHECK REFRIGERANT PRESSURE SENSOR IN PUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 70 and refrigerant pressure sensor terminal 2.
Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 9.
NG >> GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E5, F14
• Harness for open or short between ECM and refrigerant pressure sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
9.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
OK or NG
OK >> Replace refrigerant pressure sensor.
NG >> Repair or replace. Continuity should exist.
Revision: March 2010
2008 QX56

EC-426
< ECU DIAGNOSIS >[VK56DE]
ECM
ECU DIAGNOSIS
ECM
CONSULT-lll Reference Valu
e in Data Monitor ModeINFOID:0000000001351350
Remarks:
z Specification data are reference values.
z Specification data are output/input values which are detected or supplied by the ECM at the connector.
* Specification data may not be directly relate d to their components signals/values/operations.
i.e. Adjust ignition timing with a timing light before monitoring IGN TIMING, because the monitor may show the specification data in spite of the
ignition timing not being adjusted to the specification data. This IGN TIMING moni tors the data calculated by the ECM according to the signals
input from the camshaft position sensor and other ignition timing related sensors.
MONITOR ITEM CONDITION SPECIFICATION
ENG SPEED • Run engine and compare CONSULT-IIl value with the tachometer indica-
tion. Almost the same speed as the
tachometer indication.
MAS A/F SE-B1 See EC-75
.
B/FUEL SCHDL See EC-75
.
A/F ALPHA-B1
A/F ALPHA-B2 See
EC-75
.
COOLAN TEMP/S • Engine: After warming up More than 70°C (158 °F)
A/F SEN1 (B1)
A/F SEN1 (B2) • Engine: After warming up Maintaining engine speed at 2,000 rpm Fluctuates around 2.2 V
HO2S2 (B1)
HO2S2 (B2) • Revving engine from idle to 3,000 rpm quickly after the following conditions
are met.
- Engine: After warming up
- Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and
at idle for 1 minute under no load 0 - 0.3V ←→
Approx. 0.6 - 1.0V
HO2S2 MNTR (B1)
HO2S2 MNTR (B2) • Revving engine from idle to 3,000 rpm quickly after the following conditions
are met.
- Engine: After warming up
- Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and at idle for 1 minute under no load LEAN
←→ RICH
VHCL SPEED SE • Turn drive wheels and compare CONSULT-IIl value with the speedometer
indication. Almost the same speed as the
speedometer indication
BATTERY VOLT • Ignition switch: ON (Engine stopped) 11 - 14V
ACCEL SEN 1 • Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released 0.5 - 1.0V
Accelerator pedal: Fully depressed 4.2 - 4.8V
ACCEL SEN 2*
1• Ignition switch: ON (Engine stopped) Accelerator pedal: Fully released 0.5 - 1.0V
Accelerator pedal: Fully depressed 4.2 - 4.8V
TP SEN 1-B1
TP SEN 2-B1 • Ignition switch: ON
(Engine stopped)
• Selector lever: D Accelerator pedal:
Fully released More than 0.36V
Accelerator pedal: Fully depressed Less than 4.75V
EVAP SYS PRES • Ignition switch: ON Approx. 1.8 - 4.8V
START SIGNAL • Ignition switch: ON → START → ON OFF → ON → OFF
CLSD THL POS • Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released ON
Accelerator pedal: Slightly depressed OFF
AIR COND SIG • Engine: After warming up, idle the
engine Air conditioner switch: OFF
OFF
Air conditioner switch: ON
(Compressor operates.) ON
P/N POSI SW • Ignition switch: ON Selector lever: P or N
ON
Selector lever: Except above OFF
PW/ST SIGNAL • Engine: After warming up, idle the
engine Steering wheel: Not being turned
(Forward direction)
OFF
Steering wheel: Being turned ON
Revision: March 2010 2008 QX56

EC-428
< ECU DIAGNOSIS >[VK56DE]
ECM
*1: Accelerator pedal position sensor 2 signal and throttle position sensor 2 signal are converted by ECM internally. Thus, the
y differ
from ECM terminals voltage signal.
*2: Before measuring the terminal voltage, confirm the battery is fully charged. Refer to PG-73
.
I/P PULLY SPD • Vehicle speed: More than 20 km/h (12 MPH)
Almost the same speed as the
tachometer indication
VEHICLE SPEED • Turn drive wheels and compare CONSULT-IIl value with the speedometer
indication. Almost the same speed as the
speedometer indication
TRVL AFTER MIL • Ignition switch: ON Vehicle has traveled after MIL has
turned ON.0 - 65,535 km
(0 - 40,723 mile)
A/F S1 HTR (B1)
A/F S1 HTR (B2) • Engine: After warming up, idle the engine
4 - 100%
AC PRESS SEN • Engine: Idle
• Both A/C switch and blower fan switch: ON (Compressor operates.)
1.0 - 4.0V
VHCL SPEED SE • Turn drive wheels and compare CONSULT-IIl value with the speedometer
indication. Almost the same speed as the
speedometer indication
SET VHCL SPD • Engine: Running ASCD: Operating.The preset vehicle speed is dis-
played.
MAIN SW • Ignition switch: ON MAIN switch: Pressed
ON
MAIN switch: Released OFF
CANCEL SW • Ignition switch: ON CANCEL switch: Pressed
ON
CANCEL switch: Released OFF
RESUME/ACC SW • Ignition switch: ON RESUME/ACCELERATE switch:
Pressed
ON
RESUME/ACCELERATE switch: Re-
leased OFF
SET SW • Ignition switch: ON SET/COAST switch: Pressed
ON
SET/COAST switch: Released OFF
DIST SW • Ignition switch: ON DISTANCE switch: Pressed
ON
DISTANCE switch: Released OFF
BRAKE SW1 • Ignition switch: ON Brake pedal: Fully released
ON
Brake pedal: Slightly depressed OFF
BRAKE SW2 • Ignition switch: ON Brake pedal: Fully released
OFF
Brake pedal: Slightly depressed ON
CRUISE LAMP • Ignition switch: ON MAIN switch: Pressed at the 1st time
→ at the 2nd timeON
→ OFF
SET LAMP • MAIN switch: ON
• Vehicle speed: Between 40 km/h
(25 MPH) and 144 km/h (89
MPH) ASCD: Operating
ON
ASCD: Not operating OFF
ALT DUTY • Engine: Idle 0 - 80%
BAT CUR SEN • Engine speed: Idle
• Battery: Fully charged*
2
• Selector lever: P or N
• Air conditioner switch: OFF
•No load Approx. 2,600 - 3,500mV
ALT DUTY SIG • Power generation voltage variable control: Operating
ON
• Power generation voltage variable control: Not operating OFF
MONITOR ITEM
CONDITION SPECIFICATION
Revision: March 2010 2008 QX56

ECM
EC-429
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ECM Harness Connector Terminal LayoutINFOID:0000000001351346
ECM Terminal and Reference ValueINFOID:0000000001351347
PREPARATION
ECM is located in the engine room passenger side behind battery.
ECM INSPECTION TABLE
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-IIl.
CAUTION:
Do not use ECM ground terminals wh
en measuring input/output voltage. Doing so may result in dam-
age to the ECMs transistor. Use a ground ot her than ECM terminals, such as the ground.
PBIB3368E
BBIA0386E
TER-
MI-
NAL
NO. WIRE
COLOR ITEM
CONDITION DATA (DC Voltage)
1 B ECM ground [Engine is running]
• Idle speedBody ground
2 LG/B A/F sensor 1 heater (bank 1) [Engine is running]
•
Warm-up condition
• Idle speed (More than 140 seconds after starting en-
gine) Approximately 2.9 - 8.8V
3L Throttle contro
l motor relay
power supply [Ignition switch: ON] BATTERY VOLTAGE
(11 - 14V)
4 L/W Throttle cont rol motor (Close)[Ignition switch: ON]
• Engine: Stopped
• Selector lever: D
• Accelerator pedal: Fully released 0 - 14V
PBIA8148J
PBIB1104E
Revision: March 2010
2008 QX56