Page 1716 of 4171
COOLING FANEC-389
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
2. Supply cooling fan motor terminals with battery voltage and
check operation.
Cooling fan motor should operate.
If NG, replace cooling fan motor.
SEF888V
Revision: December 20092009 QX56
Page 1717 of 4171
![INFINITI QX56 2009 Factory Service Manual
EC-390
< COMPONENT DIAGNOSIS >[VK56DE]
ELECTRICAL LOAD SIGNAL
ELECTRICAL LOAD SIGNAL
DescriptionINFOID:0000000003771710
The electrical load signal (Headlamp switch signal, r
ear window defogger switc INFINITI QX56 2009 Factory Service Manual
EC-390
< COMPONENT DIAGNOSIS >[VK56DE]
ELECTRICAL LOAD SIGNAL
ELECTRICAL LOAD SIGNAL
DescriptionINFOID:0000000003771710
The electrical load signal (Headlamp switch signal, r
ear window defogger switc](/manual-img/42/57031/w960_57031-1716.png)
EC-390
< COMPONENT DIAGNOSIS >[VK56DE]
ELECTRICAL LOAD SIGNAL
ELECTRICAL LOAD SIGNAL
DescriptionINFOID:0000000003771710
The electrical load signal (Headlamp switch signal, r
ear window defogger switch signal, etc.) is transferred
through the CAN communication line from BCM to ECM via IPDM E/R.
Diagnosis ProcedureINFOID:0000000003771711
1.CHECK LOAD SIGNAL CIRCUIT OVERALL FUNCTION-I
1. Turn ignition switch ON.
2. Connect CONSULT-IIl 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
Select “HEATER FAN SW” and check indication under the following conditions.
OK or NG
OK >> INSPECTION END
NG >> GO TO 6.
4.CHECK REAR WINDOW DEFOGGER SYSTEM
Refer to DEF-4
.
>> INSPECTION END
5.CHECK HEADLAMP SYSTEM
Refer to EXL-7, "System Diagram"
.
>> INSPECTION END
6.CHECK HEATER FAN CONTROL SYSTEM
Refer to HAC-50
.
Condition Indication
Rear window defogger switch: ON ON
Rear window defogger switch: OFF OFF
Condition Indication
Lighting switch: ON at 2nd position ON
Lighting switch: OFF OFF
Condition Indication
Heater fan control switch: ON ON
Heater fan control switch: OFF OFF
Revision: December 20092009 QX56
Page 1718 of 4171
ELECTRICAL LOAD SIGNALEC-391
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
>>
INSPECTION END
Revision: December 20092009 QX56
Page 1719 of 4171
![INFINITI QX56 2009 Factory Service Manual
EC-392
< COMPONENT DIAGNOSIS >[VK56DE]
FUEL INJECTOR
FUEL INJECTOR
Component DescriptionINFOID:0000000003771712
The fuel injector is a small, precise solenoid valve. When the ECM
supplies a ground to INFINITI QX56 2009 Factory Service Manual
EC-392
< COMPONENT DIAGNOSIS >[VK56DE]
FUEL INJECTOR
FUEL INJECTOR
Component DescriptionINFOID:0000000003771712
The fuel injector is a small, precise solenoid valve. When the ECM
supplies a ground to](/manual-img/42/57031/w960_57031-1718.png)
EC-392
< COMPONENT DIAGNOSIS >[VK56DE]
FUEL INJECTOR
FUEL INJECTOR
Component DescriptionINFOID:0000000003771712
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.
Diagnosis ProcedureINFOID:0000000003771713
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-IIl
1. Start engine.
2. Perform “POWER BALANCE” in “A CTIVE TEST” mode with CONSULT-IIl.
3. Make sure that each circuit produces a momentary engine speed drop.
Without CONSULT-IIl
1. Start engine.
2. Listen to each fuel injector operating sound.
Clicking noise should be heard.
OK or NG
OK >> INSPECTION END
NG >> GO TO 3.
3.CHECK FUEL INJECTOR POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
SEF375Z
PBIB1986E
Revision: December 20092009 QX56
Page 1720 of 4171
![INFINITI QX56 2009 Factory Service Manual
FUEL INJECTOREC-393
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
2. Disconnect fuel injector harness connector.
3. Turn ignition switch ON.
4. Check voltage between fuel injector INFINITI QX56 2009 Factory Service Manual
FUEL INJECTOREC-393
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
2. Disconnect fuel injector harness connector.
3. Turn ignition switch ON.
4. Check voltage between fuel injector](/manual-img/42/57031/w960_57031-1719.png)
FUEL INJECTOREC-393
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
2. Disconnect fuel injector harness connector.
3. Turn ignition switch ON.
4. Check voltage between fuel injector 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 E2, F32
IPDM E/R connector E119
15A fuse
Harness for open or short between fuel injector and fuse
>> Repair harness or connectors.
5.CHECK FUEL INJECTOR OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between fuel injector te rminal 2 and ECM terminals 21, 22, 23, 40, 41, 42, 44,
63.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
6.CHECK FUEL INJECTOR
Refer to EC-394, "Component Inspection"
.
OK or NG
OK >> GO TO 7.
NG >> Replace malfunctioning fuel injector.
7.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "How to Check Terminal"
and GI-38, "Intermittent Incident".
>> INSPECTION END
Voltage: Battery voltage
BBIA0374E
PBIB0582E
Continuity should exist.
Revision: December 20092009 QX56
Page 1721 of 4171
EC-394
< COMPONENT DIAGNOSIS >[VK56DE]
FUEL INJECTOR
Component Inspection
INFOID:0000000003771714
FUEL INJECTOR
1. Disconnect fuel injector harness connector.
2. Check resistance between terminals as shown in the figure. Resistance: 11.1 - 14.5 Ω [at 10 - 60 °C (50 - 140 °F)]
PBIB1727E
Revision: December 20092009 QX56
Page 1722 of 4171
![INFINITI QX56 2009 Factory Service Manual
FUEL PUMPEC-395
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
FUEL PUMP
DescriptionINFOID:0000000003771715
SYSTEM DESCRIPTION
*: ECM determines the start signal status by the signa INFINITI QX56 2009 Factory Service Manual
FUEL PUMPEC-395
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
FUEL PUMP
DescriptionINFOID:0000000003771715
SYSTEM DESCRIPTION
*: ECM determines the start signal status by the signa](/manual-img/42/57031/w960_57031-1721.png)
FUEL PUMPEC-395
< COMPONENT DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
FUEL PUMP
DescriptionINFOID:0000000003771715
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 EC M stops pump operation and prevents battery discharging,
thereby improving safety. The ECM does not directly dr ive 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.
Diagnosis ProcedureINFOID:0000000003771716
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.
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 cranking Operates.
When engine is stopped Stops in 1.5 seconds.
Except as shown above Sto ps .
BBIA0402E
Fuel pressure pulsation should be felt on the fuel feed
hose for 1 second after ignition switch is turned ON.
BBIA0357E
Revision: December 20092009 QX56
Page 1723 of 4171
![INFINITI QX56 2009 Factory Service Manual
EC-396
< COMPONENT DIAGNOSIS >[VK56DE]
FUEL PUMP
4. Check voltage between ECM terminal 113 and ground with
CONSULT-IIl or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 3.
3.CHECK FUEL PUMP POWER SUPPLY INFINITI QX56 2009 Factory Service Manual
EC-396
< COMPONENT DIAGNOSIS >[VK56DE]
FUEL PUMP
4. Check voltage between ECM terminal 113 and ground with
CONSULT-IIl or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 3.
3.CHECK FUEL PUMP POWER SUPPLY](/manual-img/42/57031/w960_57031-1722.png)
EC-396
< COMPONENT DIAGNOSIS >[VK56DE]
FUEL PUMP
4. Check voltage between ECM terminal 113 and ground with
CONSULT-IIl 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-IIl 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.
>> Repair harness or connectors.
5.CHECK CONDENSER-2 POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.
3. Disconnect condenser-2 harness connector.
4. Turn ignition switch ON.
5. Check voltage between condenser-2 terminal 1 and ground with CONSULT-IIl or tester.
6. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> GO TO 6.
6.CHECK 15A FUSE
1. Turn ignition switch OFF. Voltage: Battery voltage
PBIB1187E
Voltage: Battery voltage
PBIB2656E
BBIA0388E
Voltage: Battery voltage should exist for 1 sec-
ond after ignition switch is turned ON.
PBIB0624E
Revision: December 20092009 QX56