2007 INFINITI QX56 engine

EC-594
< SERVICE INFORMATION >
DTC P2A00, P2A03 A/F SENSOR 1
2. Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace.
4.CLEAR THE SELF-LEARNING DATA
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT-II.
3. Clear the self-learning control coefficient by touching “CLEAR”.
4. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected?
Is it difficult to start engine?
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.
3. Disconnect mass air flow sensor harness connector.
4. Restart engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor harness con-
nector.
6. Make sure DTC P0102 is displayed.
7. Erase the DTC memory. Refer to EC-49, "
Emission-related
Diagnostic Information".
8. Make sure DTC P0000 is displayed.
9. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected?
Is it difficult to start engine?
Ye s o r N o
Yes >> Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to EC-292 or EC-301.
No >> GO TO 5.
5.CHECK HARNESS CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect A/F sensor 1 harness connector.
3. Check harness connector for water.
OK or NG
OK >> GO TO 6.
NG >> Repair or replace harness connector.
SEF968Y
BBIA0368E
Water should not exit.
BBIA0376E

EC-606
< SERVICE INFORMATION >
ELECTRICAL LOAD SIGNAL
ELECTRICAL LOAD SIGNAL
DescriptionINFOID:0000000003532157
The electrical load signal (Headlamp switch signal, rear window defogger switch signal, etc.) is transferred
through the CAN communication line from BCM to ECM via IPDM E/R.
CONSULT-II Reference Value in Data Monitor ModeINFOID:0000000003532158
Specification data are reference values.
Diagnosis ProcedureINFOID:0000000003532159
1.CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-I
1. Turn ignition switch ON.
2. Connect CONSULT-II and select “DATA MONITOR” mode.
3. Select “LOAD SIGNAL” and check indication under the following
conditions.
OK or NG
OK >> GO TO 2.
NG >> GO TO 4.
2.CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-II
Check “LOAD SIGNAL” indication under the following conditions.
OK or NG
OK >> GO TO 3.
NG >> GO TO 5.
3.CHECK HEATER FAN SIGNAL CIRCUIT OVERALL FUNCTION
MONITOR ITEM CONDITION SPECIFICATION
LOAD SIGNAL • Ignition switch: ONRear window defogger switch is ON
and/or lighting switch is in 2nd.ON
Rear window defogger switch is OFF
and lighting switch is OFF.OFF
HEATER FAN SW• Engine: After warming up, idle the
engineHeater fan control switch: ON ON
Heater fan control switch: OFF OFF
Condition Indication
Rear window defogger switch: ON ON
Rear window defogger switch: OFF OFF
PBIB0103E
Condition Indication
Lighting switch: ON at 2nd position ON
Lighting switch: OFF OFF
PBIB0103E

EC-608
< SERVICE INFORMATION >
FUEL INJECTOR
FUEL INJECTOR
Component DescriptionINFOID:0000000003532160
The fuel injector is a small, precise solenoid valve. When the ECM
supplies a ground to the fuel injector circuit, the coil in the fuel injec-
tor is energized. The energized coil pulls the ball valve back and
allows fuel to flow through the fuel injector into the intake manifold.
The amount of fuel injected depends upon the injection pulse dura-
tion. Pulse duration is the length of time the fuel injector remains
open. The ECM controls the injection pulse duration based on
engine fuel needs.
CONSULT-II Reference Value in Data Monitor ModeINFOID:0000000003532161
Specification data are reference values.
SEF375Z
MONITOR ITEM CONDITION SPECIFICATION
B/FUEL SCHDL See EC-129
.
INJ PULSE-B1
INJ PULSE-B2• Engine: After warming up
• Air conditioner switch: OFF
• Selector lever: P or N
•No loadIdle 2.0 - 2.8 msec
2,000 rpm 1.9 - 2.9 msec

EC-610
< SERVICE INFORMATION >
FUEL INJECTOR
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.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
Diagnosis ProcedureINFOID:0000000003532163
1.INSPECTION START
Turn ignition switch to START.
Is any cylinder ignited?
Ye s o r N o
Ye s > > G O T O 2 .
No >> GO TO 3.
2.CHECK OVERALL FUNCTION
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.
TER-
MI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
21
22
23
40
41
42
44
63O/L
BR
GR/W
Y/G
P
L
O
GFuel injector No. 5
Fuel injector No. 3
Fuel injector No. 1
Fuel injector No. 6
Fuel injector No. 4
Fuel injector No. 2
Fuel injector No. 7
Fuel injector No. 8[Engine is running]
•Warm-up condition
• Idle speed
NOTE:
The pulse cycle changes depending on rpm at idle. BATTERY VOLTAGE
(11 - 14V)
[Engine is running]
•Warm-up condition
• Engine speed: 2,000 rpmBATTERY VOLTAGE
(11 - 14V)
PBIB0042E
PBIB0043E
PBIB0133E

FUEL PUMP
EC-613
< SERVICE INFORMATION >
C
D
E
F
G
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L
MA
EC
N
P O
FUEL PUMP
DescriptionINFOID:0000000003532166
SYSTEM DESCRIPTION
*: ECM determines the start signal status by the signals of engine speed and battery voltage.
The ECM activates the fuel pump for several seconds after the ignition switch is turned ON to improve engine
startability. If the ECM receives a engine speed signal from the camshaft position sensor (PHASE), it knows
that the engine is rotating, and causes the pump to operate. If the engine speed signal is not received when
the ignition switch is ON, the engine stalls. The ECM stops pump operation and prevents battery discharging,
thereby improving safety. The ECM does not directly drive the fuel pump. It controls the ON/OFF fuel pump
relay, which in turn controls the fuel pump.
COMPONENT DESCRIPTION
A turbine type design fuel pump is used in the fuel tank.
CONSULT-II Reference Value in Data Monitor ModeINFOID:0000000003532167
Specification data are reference values.
Sensor Input signal to ECM ECM Function Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed*
Fuel pump control Fuel pump relay
Battery Battery voltage*
Condition Fuel pump operation
Ignition switch is turned to ON. Operates for 1 second.
Engine running and crankingOperates.
When engine is stopped Stops in 1.5 seconds.
Except as shown aboveSto ps .
BBIA0402E
MONITOR ITEM CONDITION SPECIFICATION
FUEL PUMP RLY• For 1 second after turning ignition switch ON
• Engine running or crankingON
• Except above conditions OFF

FUEL PUMP
EC-615
< SERVICE INFORMATION >
C
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F
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EC
N
P O
Diagnosis ProcedureINFOID:0000000003532169
1.CHECK OVERALL FUNCTION
1. Turn ignition switch ON.
2. Pinch fuel feed hose with two fingers.
OK or NG
OK >>INSPECTION END
NG >> GO TO 2.
2.CHECK FUEL PUMP POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Turn ignition switch ON.
4. Check voltage between ECM terminal 113 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 3.
3.CHECK FUEL PUMP POWER SUPPLY CIRCUIT-II
Check voltage between IPDM E/R terminal 46 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 13.
4.DETECT MALFUNCTIONING PART
Check harness for open or short between IPDM E/R and ECM.
TER-
MI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
11 3 G R F u e l p u m p r e l a y[Ignition switch: ON]
• For 1 second after turning ignition switch ON
[Engine is running]0 - 1.5V
[Ignition switch: ON]
• More than 1 second after turning ignition
switch ON.BATTERY VOLTAGE
(11 - 14V)
Fuel pressure pulsation should be felt on the fuel feed
hose for 1 second after ignition switch is turned ON.
BBIA0357E
Voltage: Battery voltage
PBIB1187E
Voltage: Battery voltage
PBIB2656E

EC-628
< SERVICE INFORMATION >
IGNITION SIGNAL
TER-
MI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
111 W / BECM relay
(Self shut-off)[Engine is running]
[Ignition switch: OFF]
• For a few seconds after turning ignition
switch OFF0 - 1.5V
[Ignition switch: OFF]
• More than a few seconds after turning igni-
tion switch OFFBATTERY VOLTAGE
(11 - 14V)
11 9
120BR
BRPower supply for ECM[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)

EC-630
< SERVICE INFORMATION >
IGNITION SIGNAL
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)TER-
MI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
46
60
61
62L/R
GR/R
O/W
Y/RIgnition signal No. 7
Ignition signal No. 5
Ignition signal No. 3
Ignition signal No. 1[Engine is running]
•Warm-up condition
• Idle speed
NOTE:
The pulse cycle changes depending on rpm at
idle.0 - 0.2V
[Engine is running]
•Warm-up condition
• Engine speed: 2,000 rpm.0.1 - 0.4V
PBIB0044E
PBIB0045E