Infiniti FX35, FX50 (S51). Manual - part 891

FUEL INJECTOR

EC-1105

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5.

CHECK FUEL INJECTOR

Refer to 

EC-1105, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Replace malfunctioning fuel injector.

6.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-36, "Intermittent Incident"

.

Is the inspection result normal?

YES

>> Replace IPDM E/R.

NO

>> Repair open circuit, short to ground or short to power in harness or connectors.

Component Inspection

INFOID:0000000005237610

1.

CHECK FUEL INJECTOR

1.

Turn ignition switch OFF.

2.

Disconnect fuel injector harness connector.

3.

Check resistance between fuel injector terminals as follows.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace malfunctioning fuel injector.

Terminals

Resistance

1 and 2

11.1 - 14.3 

Ω

 [at 10 - 60

°

C (50 - 140

°

F)]

PBIB1727E

EC-1106

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FUEL PUMP

FUEL PUMP

Description

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The ECM activates the fuel pump for 1 second after the ignition switch is turned ON to improve engine start-
ability. If the ECM receives a engine speed signal from the camshaft position sensor, 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 sends the control signal to the fuel pump control mod-
ule, which in turn controls the fuel pump. Refer to 

EC-675, "System Description"

.

Component Function Check

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1.

CHECK FUEL PUMP FUNCTION

1.

Turn ignition switch ON.

2.

Pinch fuel feed hose (1) with two fingers.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>>

EC-1106, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000005237613

1.

CHECK GROUND CONNECTION

1.

Turn ignition switch OFF.

2.

Check ground connection M95. Refer to Ground Inspection in 

GI-39, "Circuit Inspection"

.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair or replace ground connection.

2.

CHECK FPCM POWER SUPPLY CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect FPCM harness connector.

3.

Turn ignition switch ON.

4.

Check the voltage between FPCM harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> GO TO 3.

3.

DETECT MALFUNCTIONING PART

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

Stops.

Fuel pressure pulsation should be felt on the fuel feed 
hose for 1 second after ignition switch is turned ON.

JMBIA1562ZZ

FPCM

Ground

Voltage

Connector

Terminal

B31

10

Ground

Battery voltage

FUEL PUMP

EC-1107

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Check the following.
• Harness connectors B3, E121
• 15 A fuse (No.41)
• Harness for open or short between FPCM and IPDM E/R

>> Repair open circuit, short to ground or short to power in harness or connectors.

4.

CHECK FPCM GROUND CIRCUIT FOR OPEN AND SHORT

1.

Turn ignition switch OFF.

2.

Check the continuity between FPCM harness connector and ground.

3.

Also check harness for short to power.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Repair open circuit or short to power in harness or connectors.

5.

CHECK FPCM INPUT AND OUTPUT CIRCUITS FOR OPEN AND SHORT

1.

Disconnect ECM harness connector.

2.

Check the continuity between FPCM harness connector and ECM harness connector.

3.

Also check harness for short to ground and short to power.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> GO TO 6.

6.

DETECT MALFUNCTIONING PART

Check the following.
• Harness connectors B1, M7
• Harness for open or short between FPCM and ECM

>> Repair open circuit, short to ground or short to power in harness or connectors.

7.

CHECK FUEL PUMP CONTROL CIRCUIT FOR OPEN AND SHORT

1.

Disconnect “fuel level sensor unit and fuel pump (main)” harness connector.

2.

Check the continuity between FPCM harness connector and “fuel level sensor unit and fuel pump (main)”
harness connector.

3.

Also check harness for short to ground and short to power.

Is the inspection result normal?

YES

>> GO TO 8.

NO

>> Repair open circuit, short to ground or short to power in harness or connectors.

FPCM

Ground

Continuity

Connector

Terminal

B31

5

Ground

Existed

FPCM

ECM

Continuity

Connector

Terminal

Connector

Terminal

B31

8

M160

125

Existed

9

112

FPCM

Fuel level sensor unit and fuel pump (main)

Continuity

Connector

Terminal

Connector

Terminal

B31

6

B22

3

Existed

7

1

EC-1108

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FUEL PUMP

8.

CHECK FUEL PUMP

Refer to 

EC-1108, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> Replace fuel pump.

9.

CHECK FPCM

Refer to 

EC-1001, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 10.

NO

>> Replace FPCM.

10.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-36, "Intermittent Incident"

.

>> INSPECTION END

Component Inspection

INFOID:0000000005237614

1.

CHECK FUEL PUMP

1.

Turn ignition switch OFF.

2.

Disconnect “fuel level sensor unit and fuel pump (main)” harness connector.

3.

Check resistance between “fuel level sensor unit and fuel pump (main)” terminals as follows.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace “fuel level sensor unit and fuel pump (main)”

Terminals

Resistance

1 and 3

0.2 - 5.0 

Ω

 [at 25

°

C (77

°

F)]