Infiniti Q45. Manual - part 420

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION

EC-319

C

D

E

F

G

H

I

J

K

L

M

A

EC

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 

COLOR

ITEM

CONDITION

DATA (DC Voltage)

2

OR

A/F sensor 1 heater
(bank 1)

[Engine is running]

●

Warm-up condition

●

Idle speed

Approximately 5V

16

W

A/F sensor 1 (bank 1)

[Engine is running]

●

Warm-up condition

●

Idle speed

Approximately 3.1V

35

R

Approximately 2.6V

56

R/L

Approximately 2.3V

75

BR

Approximately 2.3V

21
22
23
44

W/B
Y
R/L
BR

Fuel 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 idle

BATTERY VOLTAGE

(11 - 14V)

[Engine is running]

●

Warm-up condition

●

Engine speed: 2,000 rpm

BATTERY VOLTAGE

(11 - 14V)

PBIB1584E

PBIB0042E

PBIB0043E

EC-320

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION

BANK 2

TBWM1229E

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION

EC-321

C

D

E

F

G

H

I

J

K

L

M

A

EC

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 

COLOR

ITEM

CONDITION

DATA (DC Voltage)

24

SB

A/F sensor 1 heater
(bank 2)

[Engine is running]

●

Warm-up condition

●

Idle speed

Approximately 5V

40
41
42
63

BR
G
B/R
L

Fuel 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 idle

BATTERY VOLTAGE

(11 - 14V)

[Engine is running]

●

Warm-up condition

●

Engine speed: 2,000 rpm

BATTERY VOLTAGE

(11 - 14V)

57

G/Y

A/F sensor 1 (bank 2)

[Engine is running]

●

Warm-up condition

●

Idle speed

Approximately 2.6V

58

G

Approximately 2.3V

76

L/W

Approximately 3.1V

77

GY

Approximately 2.3V

PBIB1584E

PBIB0042E

PBIB0043E

EC-322

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION

Diagnostic Procedure

NBS001V9

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

1.

Listen for an intake air leak after the mass air flow sensor.

2.

Check PCV hose connection.

OK or NG

OK

>> GO TO 3.

NG

>> Repair or replace.

PBIB1216E