2004 INFINITI FX35 Abs

EC-1280
[VK45DE]
FUEL PUMP CIRCUIT
Revision: 2004 November 2004 FX35/FX45
FUEL PUMP CIRCUITPFP:17042
DescriptionABS00CEU
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 ModeABS00CEV
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 stoppedStops in 1.5 seconds.
Except as shown aboveSto ps.
PBIB1508E
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 CIRCUIT
EC-1281
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
Wiring DiagramABS00CEW
TBWH0112E

EC-1282
[VK45DE]
FUEL PUMP CIRCUIT
Revision: 2004 November 2004 FX35/FX45
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 ProcedureABS00CEX
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)
11 3 G Y / 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 ONBATTERY VOLTAGE
(11 - 14V)
PBIB1491E
Voltage: Battery voltage
PBIB1187E

FUEL PUMP CIRCUIT
EC-1285
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
11 . 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 harness connector E206, B6.
4. Check harness continuity between “fuel level sensor unit and
fuel pump” terminal 1 and harness connector B6 terminal 4, “fuel
level sensor 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 13.
NG >> GO TO 12.
12. DETECT MALFUNCTIONING PART
Check the following.

Harness connector B6

Harness for open or short between “fuel level sensor unit and fuel pump” and harness connector B6

Harness for open or short between “fuel level sensor unit and fuel pump” and ground
>> Repair open circuit or short to ground or short to power in harness or connectors.
13. CHECK FUEL PUMP
Refer to EC-1285, "
Component Inspection" .
OK or NG
OK >> GO TO 14.
NG >> Replace fuel pump.
14. CHECK INTERMITTENT INCIDENT
Refer to EC-784, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
OK or NG
OK >> Replace IPDM E/R.
NG >> Repair or replace harness or connectors.
Component InspectionABS00CEY
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.Continuity should exist.
PBIB1507E
Resistance: Approximately 0.2 - 5.0Ω [at 25°C (77°F)]
SEC918C

EC-1286
[VK45DE]
FUEL PUMP CIRCUIT
Revision: 2004 November 2004 FX35/FX45
CONDENSER
1. Turn ignition switch OFF.
2. Disconnect condenser harness connector.
3. Check resistance between condenser terminals as 1 and 2.
Removal and InstallationABS00CEZ
FUEL PUMP
Refer to FL-4, "FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY" .
Resistance Above 1 MΩ at 25°C (77°F)
PBIB0794E

REFRIGERANT PRESSURE SENSOR
EC-1287
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
REFRIGERANT PRESSURE SENSORPFP:92136
Component DescriptionABS00CF0
The refrigerant pressure sensor is installed at the condenser of the
air conditioner system. The sensor uses an electrostatic volume
pressure transducer to convert refrigerant pressure to voltage. The
voltage signal is sent to ECM, and ECM controls cooling fan system.
PBIB1492E
PBIB2657E

EC-1288
[VK45DE]
REFRIGERANT PRESSURE SENSOR
Revision: 2004 November 2004 FX35/FX45
Wiring DiagramABS00CF1
TBWM0265E

REFRIGERANT PRESSURE SENSOR
EC-1289
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
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 ProcedureABS00CF2
1. CHECK REFRIGERANT PRESSURE SENSOR OVERALL FUNCTION
1. Start engine and warm it up to normal operating temperature.
2. Turn A/C switch and blower switch ON.
3. Check voltage between ECM terminal 70 and ground with CON-
SULT-II or tester.
OK or NG
OK >>INSPECTION END
NG >> GO TO 2.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
49 PUSensor power supply
(Refrigerant pressure sen-
sor)[Ignition switch: ON]Approximately 5V
67 B/WSensor ground
(Mass air flow sensor / IAT
sensor / Power steering
pressure sensor / EVAP
control system pressure
sensor / Refrigerant pres-
sure sensor / ECT sensor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
70 L/R Refrigerant pressure sensor[Engine is running]

Warm-up condition

Both A/C switch and blower switch are ON
(Compressor operates)1.0 - 4.0V
Voltage: 1.0 - 4.0V
PBIB1188E