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EC-1032
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DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
Revision: 2007 April2007 M35/M45
10. CHECK INTERMITTENT INCIDENT
Refer to EC-857, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
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![INFINITI M35 2007 Factory Service Manual DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
EC-1033
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DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTIONPFP:16600
On Board Diagnosis INFINITI M35 2007 Factory Service Manual DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
EC-1033
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DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTIONPFP:16600
On Board Diagnosis](/manual-img/42/57024/w960_57024-2561.png)
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
EC-1033
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DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTIONPFP:16600
On Board Diagnosis LogicNBS005FD
With the Air/Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the
theoretical mixture ratio based on the mixture ratio feedback signal from the A/F sensors 1. The ECM calcu-
lates the necessary compensation to correct the offset between the actual and the theoretical ratios.
In case the amount of the compensation value is extremely large (The actual mixture ratio is too rich.), the
ECM judges the condition as the fuel injection system malfunction and lights up the MIL (2 trip detection logic).
DTC Confirmation ProcedureNBS005FE
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. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON and select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CON-
SULT-II.
4. Clear the self-learning control coefficient by touching “CLEAR”.
5. Select “DATA MONITOR” mode with CONSULT-II.
6. Start engine again and let it idle for at least 10 minutes.
The 1st trip DTC P0172, P0175 should be detected at this stage,
if a malfunction exists. If so, go to EC-1039, "
Diagnostic Proce-
dure" .
NOTE:
If 1st trip DTC is not detected during above procedure, perform-
ing the following procedure is advised.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Start engine and drive the vehicle under the similar conditions to
(1st trip) Freeze Frame Data for 10 minutes. Refer to the table below.
Hold the accelerator pedal as steady as possible.
The similar conditions to (1st trip) Freeze Frame Data means the vehicle operation that the following con-
ditions should be satisfied at the same time.
7. If it is difficult to start engine at step 6, the fuel injection system has a malfunction, too.
8. Crank engine while depressing accelerator pedal.
Sensor Input signal to ECM ECM function Actuator
A/F sensor 1Density of oxygen in exhaust gas
(Mixture ratio feedback signal)Fuel injection control Fuel injector
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0172
0172
(Bank 1)
Fuel injection system too
rich
Fuel injection system does not operate properly.
The amount of mixture ratio compensation is too
large. (The mixture ratio is too rich.)
A/F sensor 1
Fuel injector
Exhaust gas leaks
Incorrect fuel pressure
Mass air flow sensor P0175
0175
(Bank 2)
SEF968Y
Engine speed Engine speed in the freeze frame data ± 400 rpm
Vehicle speed Vehicle speed in the freeze frame data ± 10 km/h (6 MPH)
Engine coolant temperature
(T) conditionWhen the freeze frame data shows lower than 70 °C (158 °F),
T should be lower than 70 °C (158 °F).
When the freeze frame data shows higher than or equal to 70 °C (158 °F),
T should be higher than or equal to 70 °C (158 °F).
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![INFINITI M35 2007 Factory Service Manual EC-1034
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DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2007 April2007 M35/M45
If engine starts, go to EC-1039, "Diagnostic Procedure" . If engine does not start, remove spark plugs INFINITI M35 2007 Factory Service Manual EC-1034
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DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2007 April2007 M35/M45
If engine starts, go to EC-1039, "Diagnostic Procedure" . If engine does not start, remove spark plugs](/manual-img/42/57024/w960_57024-2562.png)
EC-1034
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DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
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If engine starts, go to EC-1039, "Diagnostic Procedure" . If engine does not start, remove spark plugs and
check for fouling, etc.
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Disconnect mass air flow sensor (1) harness connector. Then
restart and run engine for at least 5 seconds at idle speed.
4. Stop engine and reconnect mass air flow sensor harness con-
nector.
5. Select Service $03 with GST. Make sure DTC P0102 is
detected.
6. Select Service $04 with GST and erase the DTC P0102.
7. Start engine again and let it idle for at least 10 minutes.
8. Select Service $07 with GST. The 1st trip DTC P0172 or P0175
should be detected at this stage, if a malfunction exists. If so, go
to EC-1039, "
Diagnostic Procedure" .
NOTE:
If 1st trip DTC is not detected during above procedure, performing the following procedure is advised.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Start engine and drive the vehicle under the similar conditions to (1st trip) Freeze Frame Data for 10 min-
utes. Refer to the table below.
Hold the accelerator pedal as steady as possible.
The similar conditions to (1st trip) Freeze Frame Data means the vehicle operation that the following con-
ditions should be satisfied at the same time.
9. If it is difficult to start engine at step 7, the fuel injection system has a malfunction.
10. Crank engine while depressing accelerator pedal.
If engine starts, go to EC-1039, "
Diagnostic Procedure" . If engine does not start, remove spark plugs and
check for fouling, etc.
PBIB2682E
Engine speed Engine speed in the freeze frame data ± 400 rpm
Vehicle speed Vehicle speed in the freeze frame data ± 10 km/h (6 MPH)
Engine coolant temperature
(T) conditionWhen the freeze frame data shows lower than 70 °C (158 °F),
T should be lower than 70 °C (158 °F).
When the freeze frame data shows higher than or equal to 70 °C (158 °F),
T should be higher than or equal to 70 °C (158 °F).
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Wiring DiagramNBS005FF
BANK 1
TBWT1492E
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![INFINITI M35 2007 Factory Service Manual EC-1036
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DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2007 April2007 M35/M45
Specification data are reference values and are measured between each terminal and ground.
Pulse signa INFINITI M35 2007 Factory Service Manual EC-1036
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DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2007 April2007 M35/M45
Specification data are reference values and are measured between each terminal and ground.
Pulse signa](/manual-img/42/57024/w960_57024-2564.png)
EC-1036
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DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2007 April2007 M35/M45
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
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.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
2SBA/F sensor 1 heater
(bank 1)[Engine is running]
Warm-up condition
Idle speedApproximately 5V
16 W/L
A/F sensor 1 (bank 1)[Engine is running]
Warm-up condition
Idle speedApproximately 3.1V
35 GR/LApproximately 2.6V
56 LG/BApproximately 2.3V
75 YApproximately 2.3V
21
22
23
44W/B
R/Y
R/B
OFuel injector No. 5
Fuel injector No. 3
Fuel injector No. 1
Fuel injector No. 7[Engine is running]
Warm-up condition
Idle speed
NOTE:
The pulse cycle changes depending on rpm
at idleBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
Warm-up condition
Engine speed: 2,000 rpmBATTERY VOLTAGE
(11 - 14V)
PBIB1584E
PBIB0042E
PBIB0043E
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BANK 2
TBWT1493E
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![INFINITI M35 2007 Factory Service Manual EC-1038
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DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2007 April2007 M35/M45
Specification data are reference values and are measured between each terminal and ground.
Pulse signa INFINITI M35 2007 Factory Service Manual EC-1038
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DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2007 April2007 M35/M45
Specification data are reference values and are measured between each terminal and ground.
Pulse signa](/manual-img/42/57024/w960_57024-2566.png)
EC-1038
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DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
Revision: 2007 April2007 M35/M45
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
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.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
24 SBA/F sensor 1 heater
(bank 2)[Engine is running]
Warm-up condition
Idle speedApproximately 5V
40
41
42
63V/R
P/L
R/W
G/YFuel injector No. 6
Fuel injector No. 4
Fuel injector No. 2
Fuel injector No. 8[Engine is running]
Warm-up condition
Idle speed
NOTE:
The pulse cycle changes depending on rpm
at idleBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
Warm-up condition
Engine speed: 2,000 rpmBATTERY VOLTAGE
(11 - 14V)
57 BR/W
A/F sensor 1 (bank 2)[Engine is running]
Warm-up condition
Idle speedApproximately 2.6V
58 G/OApproximately 2.3V
76 G/WApproximately 3.1V
77 GRApproximately 2.3V
PBIB1584E
PBIB0042E
PBIB0043E
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Diagnostic ProcedureNBS005FG
1. CHECK EXHAUST GAS LEAK
1. Start engine and run it at idle.
2. Listen for an exhaust gas leak before three way catalyst (manifold).
OK or NG
OK >> GO TO 2.
NG >> Repair or replace.
2. CHECK FOR INTAKE AIR LEAK
Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace.
PBIB1216E