Infiniti M35/M45 Y50. Manual — part 425

DTC P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER

EC-173

[VQ35DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

BANK 2

TBWT0969E

EC-174

[VQ35DE]

DTC P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER

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.)

Diagnostic Procedure

NBS004U5

1.

CHECK GROUND CONNECTIONS

1.

Turn ignition switch OFF.

2.

Loosen and retighten two ground screws on the body.
Refer to

EC-160, "Ground Inspection"

.

OK or NG

OK

>> GO TO 2.

NG

>> Repair or replace ground connections.

TER-

MINAL

NO.

WIRE

COLOR

ITEM

CONDITION

DATA (DC Voltage)

24

O

A/F sensor 1 heater
(bank 2)

[Engine is running]

●

Warm-up condition

●

Idle speed

Approximately 5V

57

GR/L

A/F sensor 1 (bank 2)

[Engine is running]

●

Warm-up condition

●

Idle speed

Approximately 2.6V

58

LG/B

Approximately 2.3V

76

W/L

Approximately 3.1V

77

Y

Approximately 2.3V

PBIB1584E

1.

Body ground M70

2.

Body ground M16

PBIB2782E

DTC P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER

EC-175

[VQ35DE]

C

D

E

F

G

H

I

J

K

L

M

A

EC

2.

CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT

1.

Disconnect air fuel ratio (A/F) sensor 1 harness connector.

2.

Turn ignition switch ON.

3.

Check voltage between A/F sensor 1 terminal 3 and ground with
CONSULT-II or tester.

OK or NG

OK

>> GO TO 4.

NG

>> GO TO 3.

3.

DETECT MALFUNCTIONING PART

Check the following.

●

Harness connectors E12, F3

●

IPDM E/R harness connector E7

●

15A fuse

●

Harness for open or short between A/F sensor 1 and fuse

>> Repair or replace harness or connectors.

4.

CHECK A/F SENSOR 1 HEATER OUTPUT SIGNAL CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect ECM harness connector.

3.

Check harness continuity between the following;
ECM terminal 2 and A/F sensor 1 (bank 1) terminal 4 or
ECM terminal 24 and A/F sensor 1 (bank 2) terminal 4.
Refer to Wiring Diagram.

4.

Also check harness for short to ground and short to power.

OK or NG

OK

>> GO TO 5.

NG

>> Repair open circuit or short to ground or short to power in harness or connectors.

Voltage: Battery voltage

PBIB2794E

PBIB1683E

Continuity should exist.

EC-176

[VQ35DE]

DTC P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER

5.

CHECK A/F SENSOR 1 HEATER

Refer to

EC-176, "Component Inspection"

.

OK or NG

OK

>> GO TO 6.

NG

>> Replace malfunctioning air fuel ratio (A/F) sensor 1.

6.

CHECK INTERMITTENT INCIDENT

Perform

EC-153, "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT"

.

>> INSPECTION END

Component Inspection

NBS004U6

AIR FUEL RATIO (A/F) SENSOR 1 HEATER

Check resistance between terminals 3 and 4.

Check continuity between terminals 3 and 1, 2, 5, 6, terminals 4 and
1, 2, 5, 6.

If NG, replace the air fuel ratio (A/F) sensor 1.

CAUTION:

●

Discard any air fuel ratio (A/F) sensor which has been
dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.

●

Before installing new air fuel ratio (A/F) sensor, clean
exhaust system threads using Heated Oxygen Sensor
Thread Cleaner tool J-43897-18 or J-43897-12 and approved
anti-seize lubricant.

Removal and Installation

NBS004U7

AIR FUEL RATIO (A/F) SENSOR 1

Refer to

EM-28, "EXHAUST MANIFOLD"

.

Resistance: 2.3 - 4.3

Ω

[at 25

°

C (77

°

F)]

Continuity should not exist.

PBIB1684E