Infiniti M45 (Y34). Manual - part 496

START SIGNAL

EC-673

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EC

5. 

CHECK FUSE

1.

Turn ignition switch OFF.

2.

Disconnect 10A fuse.

3.

Check 10A fuse.

OK or NG

OK

>> GO TO 6.

NG

>> Replace 10A fuse.

6. 

CHECK START SIGNAL INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.

Reconnect 10A fuse.

2.

Disconnect ECM harness connector.

3.

Disconnect ignition switch harness connector.

4.

Check harness continuity between ECM terminal 59 and ignition switch terminal 5.
Refer to Wiring Diagram.

5.

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

OK or NG

OK

>> GO TO 8.

NG

>> GO TO 7.

7. 

DETECT MALFUNCTIONING PART

Check the following.

●

Harness connectors M135, F105

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Fuse block (J/B) No.1 connector M1

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Harness for open or short between ignition switch and fuse block (J/B) No.1

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Harness for open or short between ECM and fuse block (J/B) No.1

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

8. 

CHECK INTERMITTENT INCIDENT

Refer to 

EC-132, "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT"

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>> INSPECTION END

Continuity should exist.

EC-674

FUEL PUMP CIRCUIT

FUEL PUMP CIRCUIT

PFP:17042

Description

ABS002TZ

SYSTEM DESCRIPTION

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 crankshaft position sensor (POS), 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

The fuel pump with a fuel damper is an in-tank type (the pump and
damper are located in the fuel tank).

CONSULT-II Reference Value in Data Monitor Mode

ABS002U0

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

Ignition switch

Start signal

Condition

Fuel pump operation

Ignition switch is turned to ON.

Operates for 5 seconds.

Engine running and cranking

Operates.

When engine is stopped

Stops in 1.5 seconds.

Except as shown above

Stops.

PBIB0132E

MONITOR ITEM

CONDITION

SPECIFICATION

FUEL PUMP RLY

●

For 5 seconds after turning ignition switch ON

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Engine running or cranking

ON

●

Except above conditions

OFF

FUEL PUMP CIRCUIT

EC-675

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Wiring Diagram

ABS002U1

TBWA0314E

EC-676

FUEL PUMP CIRCUIT

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 Procedure

ABS002U2

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 RELAY POWER SUPPLY CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect fuel pump relay.

3.

Turn ignition switch ON.

4.

Check voltage between terminals 2, 3 and ground with CON-
SULT-II or tester.

OK or NG

OK

>> GO TO 4.

NG

>> GO TO 3.

TER-

MINAL 

NO.

WIRE 

COLOR

ITEM

CONDITION

DATA (DC Voltage)

41

GY

Fuel pump relay

[Ignition switch: ON]

●

For a few seconds after turning ignition switch 
ON

[Engine is running]

0 - 1.0V

[Ignition switch: ON]

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More than a few seconds after turning ignition 
switch ON.

BATTERY VOLTAGE
(11 - 14V)

Fuel pressure pulsation should be felt on the fuel feed 
hose for 5 second after ignition switch is turned ON.

PBIB1122E

PBIB0040E

PBIB0185E