ignition INFINITI QX56 2006 Factory Service Manual

EC-308Revision: November 2009
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
2006 QX56
7. CHECK FUNCTION OF FUEL INJECTOR
With CONSULT-II
1. Start engine.
2. Perform “POWER BALANCE ” in “ACTIVE TEST” mode with
CONSULT-II.
3. Make sure that each circuit produces a momentary engine speed drop.
Without CONSULT-II
1. Start engine.
2. Listen to each fuel injector operating sound.
OK or NG
OK >> GO TO 8.
NG >> Perform trouble diagnosis for FUEL INJECTOR, refer to EC-598, "
FUEL INJECTOR" .
8. CHECK FUEL INJECTOR
1. Remove fuel injector assembly. Refer to EM-31, "
FUEL INJECTOR AND FUEL TUBE" .
Keep fuel hose and all fuel injectors connected to fuel injector gallery.
2. Confirm that the engine is cooled down and there are no fire hazards near the vehicle.
3. Disconnect all fuel injector harness connectors.
4. Disconnect all ignition coil harness connectors.
5. Prepare pans or saucers under each fuel injectors.
6. Crank engine for about 3 seconds. Make sure fuel does not drip from fuel injector.
OK or NG
OK (Does not drip.)>>GO TO 9.
NG (Drips.)>>Replace the fuel injectors from which fuel is dripping. Always replace O-ring with new one.
9. CHECK INTERMITTENT INCIDENT
Refer to EC-144, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>> INSPECTION END
PBIB0133E
Clicking noise should be heard.
PBIB1986E

DTC P0181 FTT SENSOREC-309
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Revision: November 2009 2006 QX56
DTC P0181 FTT SENSORPFP:22630
Component DescriptionUBS00H34
The fuel tank temperature sensor is used to detect the fuel tempera-
ture inside the fuel tank. The sensor modifies a voltage signal from
the ECM. The modified signal returns to the ECM as the fuel temper-
ature input. The sensor uses a thermistor which is sensitive to the
change in temperature. The electrical resistance of the thermistor
decreases as temperature increases.

*: This data is reference value and is measured between ECM terminal 107 (Fuel
tank temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output
voltage. Doing so may result in damage to the ECM's transistor.
Use a ground other than ECM terminals, such as the ground.
On Board Diagnosis LogicUBS00H35
DTC Confirmation ProcedureUBS00H36
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR ” mode with CONSULT-II.
3. Wait at least 10 seconds. If the result is NG, go to EC-312, "
Diagnostic Procedure" .
If the result is OK, go to following step.
4. Check “COOLAN TEMP/S ” value.
If “COOLAN TEMP/S ” is less than 60°C (140 °F), the result will
be OK.
If “COOLAN TEMP/S ” is above 60°C (140°F), go to the following
step.
5. Cool engine down until “COOLAN TEMP/S” is less than 60° C
(140 °F).
6. Wait at least 10 seconds.
7. If 1st trip DTC is detected, go to EC-312, "
Diagnostic Procedure" .
BBIA0583E
Fluid temperature
°C (°F) Voltage*
V Resistance
kΩ
20 (68) 3.52.3 - 2.7
50 (122) 2.20.79 - 0.90
SEF012P
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0181
0181 Fuel tank temperature
sensor circuit range/
performance Rationally incorrect voltage from the sensor is
sent to ECM, compared with the voltage sig-
nals from engine coolant temperature sensor
and intake air temperature sensor.

Harness or connectors
(The sensor circuit is open or shorted)

Fuel tank temperature sensor
SEF174Y

EC-312Revision: November 2009
DTC P0181 FTT SENSOR
2006 QX56
Diagnostic ProcedureUBS00H38
1. CHECK COMBINATION METER FUNCTION
Refer to DI-5, "
COMBINATION METERS" .
OK or NG
OK >> GO TO 2.
NG >> Go to DI-22, "
Fuel Level Sensor Unit Inspection" .
2. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-150, "
Ground Inspection" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace ground connections.
3. CHECK FUEL TANK TEMPERATURE SENSOR POWER SUPPLY CIRCUIT
1. Disconnect “fuel level sensor unit and fuel pump ” harness con-
nector.
2. Turn ignition switch ON.
3. Check voltage between “fuel level sensor unit and fuel pump” terminal 4 and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
BBIA0354E
BBIA0583E
Voltage: Approximately 5V
PBIB0932E

DTC P0181 FTT SENSOREC-313
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Revision: November 2009 2006 QX56
4. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors C1, E41

Harness for open or short between ECM and “fuel level sensor unit and fuel pump”
>> Repair harness or connector.
5. CHECK FUEL TANK TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect combination meter harness connector.
3. Check harness continuity between “fuel level sensor unit and fuel pump” terminal 3 and combination
meter terminal 16. 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.
6. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors C1, E41

Harness connectors E152, M31

Harness for open or short between “fuel level sensor unit and fuel pump ” and combination meter
>> Repair open circuit or short to ground or short to power in harness or connector.
7. CHECK FUEL TANK TEMPERATURE SENSOR
Refer to EC-314, "
Component Inspection" .
OK or NG
OK >> GO TO 8.
NG >> Replace “fuel level sensor unit and fuel pump ”.
8. CHECK INTERMITTENT INCIDENT
Refer to EC-144, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>> INSPECTION END
Continuity should exist.

DTC P0182, P0183 FTT SENSOREC-315
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Revision: November 2009 2006 QX56
DTC P0182, P0183 FTT SENSORPFP:22630
Component DescriptionUBS00H3B
The fuel tank temperature sensor is used to detect the fuel tempera-
ture inside the fuel tank. The sensor modifies a voltage signal from
the ECM. The modified signal returns to the ECM as the fuel temper-
ature input. The sensor uses a thermistor which is sensitive to the
change in temperature. The electrical resistance of the thermistor
decreases as temperature increases.

*: This data is reference value and is measured between ECM terminal 107 (Fuel
tank temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output
voltage. Doing so may result in damage to the ECM's transistor.
Use a ground other than ECM terminals, such as the ground.
On Board Diagnosis LogicUBS00H3C
DTC Confirmation ProcedureUBS00H3D
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR ” mode with CONSULT-II.
3. Wait at least 5 seconds.
4. If 1st trip DTC is detected, go to EC-317, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
BBIA0583E
Fluid temperature
°C (°F) Voltage*
V Resistance
kΩ
20 (68) 3.52.3 - 2.7
50 (122) 2.20.79 - 0.90
SEF012P
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0182
0182 Fuel tank temperature
sensor circuit low input An excessively low voltage from the sensor is
sent to ECM.

Harness or connectors
(The sensor circuit is open or shorted.)

Fuel tank temperature sensor
P0183
0183 Fuel tank temperature
sensor circuit high input An excessively high voltage from the sensor is
sent to ECM.
SEF174Y

DTC P0182, P0183 FTT SENSOREC-317
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Revision: November 2009 2006 QX56
Diagnostic ProcedureUBS00H3F
1. CHECK COMBINATION METER FUNCTION
Refer to DI-5, "
COMBINATION METERS" .
OK or NG
OK >> GO TO 2.
NG >> Go to DI-22, "
Fuel Level Sensor Unit Inspection" .
2. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-150, "
Ground Inspection" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace ground connections.
3. CHECK FUEL TANK TEMPERATURE SENSOR POWER SUPPLY CIRCUIT
1. Disconnect “fuel level sensor unit and fuel pump ” harness con-
nector.
2. Turn ignition switch ON.
3. Check voltage between “fuel level sensor unit and fuel pump ”
terminal 4 and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
BBIA0354E
BBIA0583E
Voltage: Approximately 5V
PBIB0932E

EC-318Revision: November 2009
DTC P0182, P0183 FTT SENSOR
2006 QX56
4. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors C1, E41

Harness for open or short between ECM and “fuel level sensor unit and fuel pump ”
>> Repair harness or connector.
5. CHECK FUEL TANK TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect combination meter harness connector.
3. Check harness continuity between “fuel level sensor unit and fuel pump” terminal 3 and combination
meter terminal 16. 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.
6. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors C1, E41

Harness connectors E152, M31

Harness for open or short between “fuel level sensor unit and fuel pump” and combination meter
>> Repair open circuit or short to ground or short to power in harness or connector.
7. CHECK FUEL TANK TEMPERATURE SENSOR
Refer to EC-319, "
Component Inspection" .
OK or NG
OK >> GO TO 8.
NG >> Replace “fuel level sensor unit and fuel pump ”.
8. CHECK INTERMITTENT INCIDENT
Refer to EC-144, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>> INSPECTION END
Continuity should exist.

EC-320Revision: November 2009
DTC P0222, P0223 TP SENSOR
2006 QX56
DTC P0222, P0223 TP SENSORPFP:16119
Component DescriptionUBS00H3I
Electric throttle control actuator consists of throttle control motor,
throttle position sensor, etc. The throttle position sensor responds to
the throttle valve movement.
The throttle position sensor has the two sensors. These sensors are
a kind of potentiometers which transform the throttle valve position
into output voltage, and emit the voltage signal to the ECM. In addi-
tion, these sensors detect the opening and closing speed of the
throttle valve and feed the voltage signals to the ECM. The ECM
judges the current opening angle of the throttle valve from these sig-
nals and the ECM controls the throttle control motor to make the
throttle valve opening angle properly in response to driving condi-
tion.
CONSULT-II Reference Value in Data Monitor ModeUBS00H3J
Specification data are reference values.
*: Throttle position sensor 2 signal is converted by ECM internally. Thus, it differs from ECM terminal voltage signal.
On Board Diagnosis LogicUBS00H3K
These self-diagnoses have the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
PBIB0145E
MONITOR ITEMCONDITION SPECIFICATION
THRTL SEN 1
THRTL SEN 2*

Ignition switch: ON
(Engine stopped)

Selector lever: D Accelerator pedal: Fully released More than 0.36V
Accelerator pedal: Fully depressed Less than 4.75V
DTC No. Trouble diagnosis name
DTC detecting condition Possible cause
P0222
0222 Throttle position sensor
1 circuit low input An excessively low voltage from the TP sensor
1 is sent to ECM.

Harness or connectors
(TP sensor 1 circuit is open or shorted.)
(APP sensor 2 circuit is shorted.)

Electric throttle control actuator
(TP sensor 1)

Accelerator pedal position sensor
(APP sensor 2)
P0223
0223
Throttle position sensor
1 circuit high input An excessively high voltage from the TP sensor
1 is sent to ECM.
Engine operation condition in fail-safe mode
The ECM controls the electric throttle control actuator in regulating the throttle opening in order for the idle position to be within +10
degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal condition.
So, the acceleration will be poor.

DTC P0222, P0223 TP SENSOREC-321
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Revision: November 2009 2006 QX56
DTC Confirmation ProcedureUBS00H3L
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8V at idle.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR ” mode with CONSULT-II.
3. Start engine and let it idle for 1 second.
4. If DTC is detected, go to EC-323, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
SEF058Y

DTC P0222, P0223 TP SENSOREC-323
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Revision: November 2009 2006 QX56
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
Diagnostic ProcedureUBS00H3N
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-150, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TER-
MINAL NO. WIRE
COLOR ITEM
CONDITION DATA (DC Voltage)
47 Y Sensor power supply
(Throttle position sensor) [Ignition switch: ON]
Approximately 5V
50 B Throttle position sensor 1 [Ignition switch: ON]

Engine: Stopped

Selector lever: D

Accelerator pedal: Fully released
More than 0.36V
[Ignition switch: ON]

Engine: Stopped

Selector lever: D

Accelerator pedal: Fully depressed Less than 4.75V
66 R Sensor ground
(Throttle position sensor) [Engine is running]

Warm-up condition

Idle speed
Approximately 0V
69 W Throttle position sensor 2 [Ignition switch: ON]

Engine: Stopped

Selector lever: D

Accelerator pedal: Fully released
Less than 4.75V
[Ignition switch: ON]

Engine: Stopped

Selector lever: D

Accelerator pedal: Fully depressed More than 0.36V
91 W/R Sensor power supply
(APP sensor 2) [Ignition switch: ON]
Approximately 5V
BBIA0354E