Ins INFINITI QX56 2004 Factory Service Manual

EC-592Revision: August 2007
IGNITION SIGNAL
2004 QX56
8. CHECK CONDENSER GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between condenser terminal 2 and engine ground.
Refer to Wiring Diagram.
3. 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
Refer to EC-593, "
Component Inspection" .
OK or NG
OK >> GO TO 10.
NG >> Replace condenser.
10. CHECK IGNITION COIL POWER SUPPLY CIRCUIT-IV
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.
3. Disconnect ignition coil harness connector.
4. Turn ignition switch ON.
5. Check voltage between ignition coil terminal 3 and ground with
CONSULT-II or tester.
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 . DETECT MALFUNCTIONING PART
Check the following.

Harness connectors E2, F32

Harness for open or short between ignition coil and harness connector F32
>> Repair or replace harness or connectors. Continuity should exist.
Voltage: Battery voltage
BBIA0359E
PBIB0138E

IGNITION SIGNAL
EC-593
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Revision: August 20072004 QX56
12. CHECK IGNITION COIL GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between ignition coil terminal 2 and engine ground.
Refer to Wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 13.
NG >> Repair open circuit or short to power in harness or connectors.
13. CHECK IGNITION COIL OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminals 46, 60, 61, 62, 65, 79, 80, 81 and ignition coil terminal
1.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 14.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
14. CHECK IGNITION COIL WITH POWER TRANSISTOR
Refer to EC-593, "
Component Inspection" .
OK or NG
OK >> GO TO 15.
NG >> Replace ignition coil with power transistor.
15. CHECK INTERMITTENT INCIDENT
Refer to EC-127, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionUBS00HD3
IGNITION COIL WITH POWER TRANSISTOR
1. Turn ignition switch OFF.
2. Disconnect ignition coil harness connector.
3. Check resistance between ignition coil terminals as follows.
CONDENSER
1. Turn ignition switch OFF.
2. Disconnect condenser harness connector.Continuity should exist.
Continuity should exist.
Terminal No. (Polarity) Resistance Ω [at 25°C (77°F)]
1 and 2 Except 0 or ∞
1 and 3
Except 0
2 and 3
PBIB0847E

EC-594Revision: August 2007
IGNITION SIGNAL
2004 QX56
3. Check resistance between condenser terminals 1 and 2.
Removal and InstallationUBS00HD4
IGNITION COIL WITH POWER TRANSISTOR
Refer to EM-26, "IGNITION COIL" .
Resistance Above 1 MΩ at 25°C (77°F)
PBIB0794E

INJECTOR CIRCUIT
EC-595
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Revision: August 20072004 QX56
INJECTOR CIRCUITPFP:16600
Component DescriptionUBS00HD5
The fuel injector is a small, precise solenoid valve. When the ECM
supplies a ground to the injector circuit, the coil in the injector is
energized. The energized coil pulls the needle valve back and allows
fuel to flow through the injector into the intake manifold. The amount
of fuel injected depends upon the injection pulse duration. Pulse
duration is the length of time the injector remains open. The ECM
controls the injection pulse duration based on engine fuel needs.
CONSULT-II Reference Value in Data Monitor ModeUBS00HD6
Specification data are reference values.
SEF 3 75 Z
MONITOR ITEM CONDITION SPECIFICATION
B/FUEL SCHDL

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

No loadIdle 3.0 - 4.2 msec
2,000 rpm 3.0 - 4.2 msec
INJ PULSE-B1
INJ PULSE-B2

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

No loadIdle 2.0 - 2.8 msec
2,000 rpm 1.9 - 2.9 msec

INJECTOR CIRCUIT
EC-597
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Revision: August 20072004 QX56
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
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.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
Diagnostic ProcedureUBS00HD8
1. INSPECTION START
Turn ignition switch to START.
Is any cylinder ignited?
Ye s o r N o
Yes >> GO TO 2.
No >> GO TO 3.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
21
22
23
40
41
42
44
63O/L
BR
GR/W
Y/G
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GInjector No. 5
Injector No. 3
Injector No. 1
Injector No. 6
Injector No. 4
Injector No. 2
Injector No. 7
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 is 2,000 rpmBATTERY VOLTAGE
(11 - 14V)
PBIB0042E
PBIB0043E

EC-598Revision: August 2007
INJECTOR CIRCUIT
2004 QX56
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.
2. Listen to each injector operating sound.
Clicking noise should be heard.
OK or NG
OK >>INSPECTION END
NG >> GO TO 3.
PBIB0133E
PBIB1986E

EC-600Revision: August 2007
INJECTOR CIRCUIT
2004 QX56
6. CHECK INJECTOR
Refer to EC-600, "
Component Inspection" .
OK or NG
OK >> GO TO 7.
NG >> Replace injector.
7. CHECK INTERMITTENT INCIDENT
Refer to EC-127, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionUBS00HD9
INJECTOR
1. Disconnect injector harness connector.
2. Check resistance between terminals as shown in the figure.
Removal and InstallationUBS00HDA
INJECTOR
Refer to EM-29, "FUEL INJECTOR AND FUEL TUBE" . Resistance: 11.1 - 14.5Ω [at 10 - 60°C (50 - 140°F)]
PBIB1727E

FUEL PUMP CIRCUIT
EC-603
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Revision: August 20072004 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 ProcedureUBS00HDE
1. CHECK OVERALL FUNCTION
1. Turn ignition switch ON.
2. Pinch fuel feed hose with two fingers.
Fuel pressure pulsation should be felt on the fuel feed hose
for 1 second after ignition switch is turned ON.
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.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
113 GR Fuel pump relay[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)
BBIA0357E
Voltage: Battery voltage
PBIB11 87 E

FUEL PUMP CIRCUIT
EC-605
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Revision: August 20072004 QX56
6. CHECK 15A FUSE
1. Turn ignition switch OFF.
2. Disconnect 15A fuse.
3. Check 15A fuse.
OK or NG
OK >> GO TO 7.
NG >> Replace fuse.
7. CHECK CONDENSER 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 terminal 1.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 12.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
8. CHECK CONDENSER GROUND CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between condenser terminal 1 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
Refer to EC-606, "
Component Inspection" .
OK or NG
OK >> GO TO 10.
NG >> Replace condenser.
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.Continuity should exist.
Continuity should exist.
Continuity should exist.
BBIA0583E

EC-606Revision: August 2007
FUEL PUMP CIRCUIT
2004 QX56
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
>> Repair open circuit or short to ground or short to power in harness or connectors.
12. CHECK INTERMITTENT INCIDENT
Refer to EC-127, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
OK or NG
OK >> Replace IPDM E/R.
NG >> Repair or replace harness or connectors.
Component InspectionUBS00HDF
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
1. Turn ignition switch OFF.
2. Disconnect condenser harness connector.
3. Check resistance between condenser terminals as 1 and 2.
Removal and InstallationUBS00HDG
FUEL PUMP
Refer to FL-5, "FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY" . Resistance: 0.2 - 5.0Ω [at 25°C (77°F)]
SEC9 18 C
Resistance Above 1 MΩ at 25°C (77°F)
PBIB0794E