2007 INFINITI M35 fuel

EC-464
[VQ35DE]
DTC P0461 FUEL LEVEL SENSOR
Revision: 2007 April2007 M35/M45
DTC P0461 FUEL LEVEL SENSORPFP:25060
Component DescriptionNBS0051E
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
communication 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.

Fuel level sensor unit and fuel pump (1)

Fuel pressure regulator (2)

Fuel tank temperature sensor (3)
On Board Diagnosis LogicNBS0051F
NOTE:

If DTC P0461 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-161, "
DTC U1000, U1001 CAN COMMUNICATION LINE" .

If DTC P0461 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010.
Refer to EC-164, "
DTC U1010 CAN COMMUNICATION" .
Driving long distances naturally affect fuel gauge level.
This diagnosis detects the fuel gauge malfunction of the gauge not moving even after a long distance has
been driven.
Overall Function CheckNBS0051G
Use this procedure to check the overall function of the fuel level sensor function. During this check, a 1st trip
DTC might not be confirmed.
WARNING:
When performing following procedure, be sure to observe the handling of the fuel. Refer to FL-10,
"FUEL TANK" .
TESTING CONDITION:
Before starting overall function check, preparation of draining fuel and refilling fuel is required.
WITH CONSULT-II
NOTE:
Start from step 10, 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-88, "
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 OFF and wait at least 10 seconds then turn ON.
PBIB2707E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0461
0461Fuel level sensor circuit
range/performanceThe output signal of the fuel level sensor does
not change within the specified range even
though the vehicle has been driven a long dis-
tance.

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

DTC P0461 FUEL LEVEL SENSOR
EC-465
[VQ35DE]
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Revision: 2007 April2007 M35/M45
6. Select “FUEL LEVEL SE” in “DATA MONITOR” mode with CON-
SULT-II.
7. Check “FUEL LEVEL SE” output voltage and note it.
8. Select “FUEL PUMP” in “ACTIVE TEST” mode with CONSULT-
II.
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-465, "
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-88, "
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-465, "
Diagnostic Procedure" .
Diagnostic ProcedureNBS0051H
1. CHECK DTC WITH “UNIFIED METER AND A/C AMP.”
Refer to DI-31, "
SELF-DIAG RESULTS" .
OK or NG
OK >> GO TO 2.
NG >> Go to DI-22, "
Fuel Level Sensor Signal Inspection" .
2. CHECK INTERMITTENT INCIDENT
Refer to EC-153, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Removal and InstallationNBS0051I
FUEL LEVEL SENSOR
Refer to FL-4, "FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY" .
SEF195Y

EC-466
[VQ35DE]
DTC P0462, P0463 FUEL LEVEL SENSOR CIRCUIT
Revision: 2007 April2007 M35/M45
DTC P0462, P0463 FUEL LEVEL SENSOR CIRCUITPFP:25060
Component DescriptionNBS0051J
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
communication 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.

Fuel level sensor unit and fuel pump (1)

Fuel pressure regulator (2)

Fuel tank temperature sensor (3)
On Board Diagnosis LogicNBS0051K
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-161, "
DTC U1000, U1001 CAN COMMUNICATION LINE" .

If DTC P0462 or P0463 is displayed with DTC U1010, first perform the trouble diagnosis for DTC
U1010. Refer to EC-164, "
DTC U1010 CAN COMMUNICATION" .
This diagnosis indicates the former, to detect open or short circuit malfunction.
DTC Confirmation ProcedureNBS0051L
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-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Wait at least 5 seconds.
4. If 1st trip DTC is detected, go to EC-467, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
PBIB2707E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0462
0462Fuel level sensor circuit
low inputAn excessively low voltage 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 from the sensor is
sent to ECM.
SEF195Y

DTC P0462, P0463 FUEL LEVEL SENSOR CIRCUIT
EC-467
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Revision: 2007 April2007 M35/M45
Diagnostic ProcedureNBS0051M
1. CHECK DTC WITH “UNIFIED METER AND A/C AMP.”
Refer to DI-31, "
SELF-DIAG RESULTS" .
OK or NG
OK >> GO TO 2.
NG >> Go to DI-22, "
Fuel Level Sensor Signal Inspection" .
2. CHECK INTERMITTENT INCIDENT
Refer to EC-153, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Removal and InstallationNBS0051N
FUEL LEVEL SENSOR
Refer to FL-4, "FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY" .

DTC P0500 VSS
EC-469
[VQ35DE]
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Revision: 2007 April2007 M35/M45
5. Maintain the following conditions for at least 50 consecutive sec-
onds.
6. If 1st trip DTC is detected, go to EC-469, "
Diagnostic Procedure"
.
Overall Function CheckNBS0051R
Use this procedure to check the overall function of the vehicle speed sensor circuit. During this check, a 1st
trip DTC might not be confirmed.
WITH GST
1. Lift up drive wheels.
2. Start engine.
3. Read vehicle speed sensor signal in Service $01 with GST.
The vehicle speed sensor on GST should be able to exceed 10 km/h (6 MPH) when rotating wheels with
suitable gear position.
4. If NG, go to EC-469, "
Diagnostic Procedure" .
Diagnostic ProcedureNBS0051S
1. CHECK DTC WITH “ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)”
Refer to BRC-10, "
TROUBLE DIAGNOSIS" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace.
2. CHECK DTC WITH “UNIFIED METER AND A/C AMP.”
Refer to DI-28, "
UNIFIED METER AND A/C AMP" .
>>INSPECTION END
ENG SPEED 1,600 - 6,000 rpm
COOLAN TEMP/S More than 70°C (158°F)
B/FUEL SCHDL 5.3 - 31.8 msec
Selector lever Except P or N position
PW/ST SIGNAL OFF
SEF196Y

DTC P0603 ECM POWER SUPPLY
EC-479
[VQ35DE]
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Revision: 2007 April2007 M35/M45
DTC P0603 ECM POWER SUPPLYPFP:23710
Component DescriptionNBS00529
Battery voltage is supplied to the ECM even when the ignition switch
is turned OFF for the ECM memory function of the DTC memory, the
air-fuel ratio feedback compensation value memory, the idle air vol-
ume learning value memory, etc.
On Board Diagnosis LogicNBS0052A
DTC Confirmation ProcedureNBS0052B
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.
WITH CONSULT-II
1. Turn ignition switch ON and wait at least 1 second.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Start engine and let it idle for 1 second.
4. Turn ignition switch OFF, wait at least 10 seconds, and then turn
ON.
5. Repeat steps 3 and 4 for four times.
6. If 1st trip DTC is detected, go to EC-481, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
PBIB1164E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0603
0603ECM power supply cir-
cuitECM back-up RAM system does not function
properly.

Harness or connectors
[ECM power supply (back-up) circuit is
open or shorted.]

ECM
SEF058Y

DTC P0850 PNP SWITCH
EC-491
[VQ35DE]
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Revision: 2007 April2007 M35/M45
DTC P0850 PNP SWITCHPFP:23006
Component DescriptionNBS0052M
When the selector lever position is P or N, park/neutral position (PNP) switch is ON.
ECM detects the position because the continuity of the line (the ON signal) exists.
CONSULT-II Reference Value in Data Monitor ModeNBS0052N
Specification data are reference values.
On Board Diagnosis LogicNBS0052O
DTC Confirmation ProcedureNBS0052P
CAUTION:
Always drive vehicle at a safe speed.
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.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “P/N POSI SW” in “DATA MONITOR” mode with CON-
SULT-II. Then check the “P/N POSI SW” signal under the follow-
ing conditions.
If NG, go to EC-494, "
Diagnostic Procedure" .
If OK, go to following step.
3. Select “DATA MONITOR” mode with CONSULT-II.
4. Start engine and warm it up to normal operating temperature.
5. Maintain the following conditions for at least 50 consecutive sec-
onds.
6. If 1st trip DTC is detected, go to EC-494, "
Diagnostic Procedure" .
MONITOR ITEM CONDITION SPECIFICATION
P/N POSI SW

Ignition switch: ONSelector lever: P or N ON
Selector lever: Except above OFF
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0850
0850Park/neutral position
switchThe signal of the park/neutral position (PNP)
switch is not changed in the process of engine
starting and driving.

Harness or connectors
[The park/neutral position (PNP) switch
circuit is open or shorted.]

Park/neutral position (PNP) switch

Unified meter and A/C amp.

TCM
Position (Selector lever) Known-good signal
N or P position ON
Except above position OFF
SEF212Y
ENG SPEED 1,400 - 6,375 rpm
COOLAN TEMP/S More than 70°C (158°F)
B/FUEL SCHDL 2.0 - 31.8 msec
VHCL SPEED SE More than 64 km/h (40 MPH)
Selector lever Suitable position
SEF213Y

EC-510
[VQ35DE]
DTC P1220 FUEL PUMP CONTROL MODULE (FPCM)
Revision: 2007 April2007 M35/M45
DTC P1220 FUEL PUMP CONTROL MODULE (FPCM)PFP:17001
DescriptionNBS0053A
SYSTEM DESCRIPTION
*: ECM determines the start signal status by the signals of engine speed and battery voltage.
This system controls the fuel pump operation. The amount of fuel flow delivered from the fuel pump is altered
between two flow rates by the FPCM operation. The FPCM determines the voltage supplied to the fuel pump
(and therefore fuel flow) according to the following conditions.
COMPONENT DESCRIPTION
The FPCM adjusts the voltage supplied to the fuel pump to control
the amount of fuel flow. When the FPCM increases the voltage sup-
plied to the fuel pump, the fuel flow is increased. When the FPCM
decreases the voltage, the fuel flow is decreased.
CONSULT-II Reference Value in Data Monitor ModeNBS0053B
Specification data are reference values.
On Board Diagnosis LogicNBS0053C
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed*
Fuel pump controlFuel pump control module
(FPCM) Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Battery Battery voltage*
Conditions Amount of fuel flow Supplied voltage

Engine cranking

Engine coolant temperature is below 10°C (50°F).

Engine is running under heavy load and high speed conditionshighBattery voltage
(11 - 14V)
Except the above low Approximately 8V
SEF387X
MONITOR ITEM CONDITION SPECIFICATION
FPCM

Engine: Cranking HI

Engine: Idle

Engine coolant temperature: More than 10°C (50°F)LOW
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1220
1220Fuel pump control module
(FPCM)An improper voltage signal from the FPCM, which
is supplied to a point between the fuel pump and
the dropping resistor, is detected by ECM.

Harness or connectors
(FPCM circuit is shorted.)

Dropping resistor

FPCM