Page 493 of 720

DTC P0461 FUEL LEVEL SENSOR
EC-493
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9. Touch “ON” and drain fuel approximately 30 (7-7/8 US gal, 6-5/8 Imp gal) and stop it.
10. Check “FUEL LEVEL SE” output voltage and note it.
11. Fill fuel into the fuel tank for 30 (7-7/8 US gal, 6-5/8 Imp gal).
12. Check “FUEL LEVEL SE” output voltage and note it.
13. Confirm whether the voltage changes more than 0.03V during step 7 to 10 and 10 to 12.
If NG, go to EC-493, "
Diagnostic Procedure" .
WITH GST
NOTE:
Start from step 8, if it is possible to confirm that the fuel cannot be drained by 30 (7-7/8 US gal, 6-5/8
Imp gal) in advance.
1. Prepare a fuel container and a spare hose.
2. Release fuel pressure from fuel line. Refer to EC-79, "
FUEL PRESSURE RELEASE" .
3. Remove the fuel feed hose on the fuel level sensor unit.
4. Connect a spare fuel hose where the fuel feed hose was removed.
5. Turn ignition switch ON.
6. Drain fuel by 30 (7-7/8 US gal, 6-5/8 Imp gal) from the fuel tank using proper equipment.
7. Confirm that the fuel gauge indication varies.
8. Fill fuel into the fuel tank for 30 (7-7/8 US gal, 6-5/8 Imp gal).
9. Confirm that the fuel gauge indication varies.
10. If NG, go to EC-493, "
Diagnostic Procedure" .
Diagnostic ProcedureNBS000AA
1. CHECK FUEL GAUGE OPERATION
Refer to DI-15, "
Self-Diagnosis Mode of Combination Meter" .
OK or NG
OK >> GO TO 2.
NG >> Follow the instruction of DI-15, "
Self-Diagnosis Mode of Combination Meter" .
2. CHECK FUEL LEVEL SENSOR AND CIRCUIT
Refer to DI-19, "
Fuel Level Sensor Signal Inspection" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace malfunctioning parts.
3. CHECK INTERMITTENT INCIDENT
Refer to EC-141, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Removal and InstallationNBS000AB
FUEL LEVEL SENSOR
Refer to FL-4, "FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY"
Page 494 of 720

EC-494
DTC P0462, P0463 FUEL LEVEL SENSOR
Revision: 2006 November2007 350Z
DTC P0462, P0463 FUEL LEVEL SENSORPFP:25060
Component DescriptionNBS006VB
The fuel level sensor is mounted in the fuel level sensor unit. The
sensor detects a fuel level in the fuel tank and transmits a signal to
the “unified meter and A/C amp.”. The “unified meter and A/C amp.”
sends the fuel level sensor signal to the ECM through CAN commu-
nication line.
It consists of two parts, one is mechanical float and the other is vari-
able resistor. Fuel level sensor output voltage changes depending on
the movement of the fuel mechanical float.
On Board Diagnosis LogicNBS000AD
NOTE:
If DTC P0462 or P0463 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis
for DTC U1000, U1001. Refer to EC-151, "
DTC U1000, U1001 CAN COMMUNICATION LINE".
If DTC P0462 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010.
Refer to EC-154, "
DTC U1010 CAN COMMUNICATION" .
This diagnosis indicates the former, to detect open or short circuit malfunction.
DTC Confirmation ProcedureNBS000AE
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at ignition
switch ON.
WITH CONSULT-III
1. Turn ignition switch ON and wait at least 5 seconds.
2. Check 1st trip DTC.
3. If 1st trip DTC is detected, go to EC-494, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III” above.
Diagnostic ProcedureNBS000AF
1. CHECK FUEL GAUGE OPERATION
Refer to DI-15, "
Self-Diagnosis Mode of Combination Meter" .
OK or NG
OK >> GO TO 2.
NG >> Follow the instruction of DI-15, "
Self-Diagnosis Mode of Combination Meter" .
1 : Fuel level sensor unit and fuel pump
2 : Fuel pressure regulator
3 : Fuel tank temperature sensor
PBIB2707E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0462
0462Fuel level sensor circuit
low inputAn excessively low voltage is sent from the
sensor is sent to ECM.
Harness or connectors
(The CAN communication line is open or
shorted)
Harness or connectors
(The sensor circuit is open or shorted)
Unified meter and A/C amp.
Fuel level sensor P0463
0463Fuel level sensor circuit
high inputAn excessively high voltage is sent from the
sensor is sent to ECM.
Page 495 of 720
DTC P0462, P0463 FUEL LEVEL SENSOR
EC-495
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2. CHECK FUEL LEVEL SENSOR AND CIRCUIT
Refer to DI-19, "
Fuel Level Sensor Signal Inspection" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace malfunctioning parts.
3. CHECK INTERMITTENT INCIDENT
Refer to EC-141, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Removal and InstallationNBS000AG
FUEL LEVEL SENSOR
Refer to FL-4, "FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY" .
Page 691 of 720

FUEL PUMP
EC-691
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Revision: 2006 November2007 350Z
FUEL PUMPPFP:17042
DescriptionNBS000HW
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-III Reference Value in Data Monitor ModeNBS000HX
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: ONOperates for 1 second.
Engine running or crankingOperates.
Engine: StoppedStops in 1.5 seconds.
Except as shown aboveStops.
1 : Fuel level sensor unit and fuel pump
2 : Fuel pressure regulator
3 : Fuel tank temperature sensor
PBIB2707E
MONITOR ITEM CONDITION SPECIFICATION
FUEL PUMP RLY
For 1 second after turning ignition switch ON
Engine running or crankingON
Except above conditions OFF
Page 692 of 720
EC-692
FUEL PUMP
Revision: 2006 November2007 350Z
Wiring DiagramNBS000HY
TBWT1679E
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FUEL PUMP
EC-693
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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 ProcedureNBS000HZ
1. CHECK OVERALL FUNCTION
1. Turn ignition switch ON.
2. Pinch fuel feed hose (1) 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.
4. Check voltage between ECM terminal 22 and ground with CON-
SULT-III or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 3.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
22 L/W 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)
Fuel pressure pulsation should be felt on the fuel feed
hose for 1 second after ignition switch is turned ON.
PBIB3524E
Voltage: Battery voltage
PBIB3583E
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EC-694
FUEL PUMP
Revision: 2006 November2007 350Z
3. CHECK FUEL PUMP POWER SUPPLY CIRCUIT-I
1. Disconnect IPDM E/R harness connector E8.
2. Check harness continuity between IPDM E/R terminal 40 and ECM terminal 22.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> GO TO 15.
4. DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E10, F1
Harness for open or short between IPDM E/R and ECM
>> Repair open circuit or short to ground or short to power in harness or connectors.
5. CHECK CONDENSER POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF.
2. Reconnect all harness connectors disconnected.
3. Disconnect condenser harness connector.
4. Turn ignition switch ON.
5. Check voltage between condenser terminal 1 and ground with
CONSULT-III or tester.
OK or NG
OK >> GO TO 9.
NG >> GO TO 6.
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.Continuity should exist.
Voltage: Battery voltage should exist for 1 sec-
ond after ignition switch is turned ON.
PBIB0624E
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FUEL PUMP
EC-695
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Revision: 2006 November2007 350Z
7. CHECK CONDENSER POWER SUPPLY CIRCUIT-II
1. Disconnect IPDM E/R harness connector E8.
2. Check harness continuity between IPDM E/R terminal 39 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 15.
NG >> GO TO 8.
8. DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E107, B3
Harness for open or short between IPDM E/R and condenser
>> Repair open circuit or short to ground or short to power in harness or connectors.
9. CHECK CONDENSER GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check harness continuity between condenser terminal 2 and ground.
Refer to Wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 11.
NG >> GO TO 10
10. DETECT MALFUNCTIONING PART
Check the following.
Harness connectors B43, T1 (Coupe models)
Harness connectors B39, D102 (Coupe models)
Harness connectors B61, T23 (Roadster models)
Harness for open or short between condenser and ground
>> Repair open circuit or short to power in harness or connectors.
11 . CHECK CONDENSER
Refer to EC-697, "
Component Inspection" .
OK or NG
OK >> GO TO 12.
NG >> Replace condenser.Continuity should exist.
Continuity should exist.