Infiniti QX56 (JA60). Manual - part 372

EC-140

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P0130, P0150 A/F SENSOR 1

4. Check harness continuity between the following terminals and ground.

Refer to Wiring Diagram.

5. Also check harness for 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.

5.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-35, "How to Check Terminal"

 and 

GI-38, "Intermittent Incident"

.

OK or NG

OK

>> GO TO 6.

NG

>> Repair or replace.

6.

REPLACE AIR FUEL RATIO (A/F) SENSOR 1

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

CAUTION:

• Discard any 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 A/F sensor, clean exhaust system threads using Oxygen Sensor Thread

Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.

>> INSPECTION END

Bank 2

1

16

2

75

Continuity should exist.

Bank 1

Bank 2

A/F sensor 1 terminal

ECM terminal

A/F sensor 1 terminal

ECM terminal

1

35

1

16

2

56

2

75

Continuity should not exist.

P0131, P0151 A/F SENSOR 1

EC-141

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P0131, P0151 A/F SENSOR 1

Component Description

INFOID:0000000005149160

The air fuel ratio (A/F) sensor 1 is a planar one-cell limit current sen-

sor. The sensor element of the A/F sensor 1 is composed an elec-

trode layer, which transports ions. It has a heater in the element.
The sensor is capable of precise measurement   = 1, but also in the

lean and rich range. Together with its control electronics, the sensor
outputs a clear, continuous signal throughout a wide   range.

The exhaust gas components diffuse through the diffusion layer at

the sensor cell. An electrode layer is applied voltage, and this current

relative oxygen density in lean. Also this current relative hydrocar-

bon density in rich.

Therefore, the A/F sensor 1 is able to indicate air fuel ratio by this

electrode layer of current. In addition, a heater is integrated in the

sensor to ensure the required operating temperature of about 800

°C

(1,472

°F).

On Board Diagnosis Logic

INFOID:0000000005149161

To judge the malfunction, the diagnosis checks that the A/F signal computed by ECM from the A/F sensor 1

signal is not inordinately low.

DTC Confirmation Procedure

INFOID:0000000005149162

NOTE:

If DTC Confirmation Procedure has been previously conducted, always perform the following procedure

before conducting the next step.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:

Before performing the following procedure, confirm that battery voltage is more than 10.5 V at idle.

WITH CONSULT-III

1. Start engine and warm it up to normal operating temperature.

2. Select “A/F SEN1 (B1)” or “A/F SEN1 (B2)” in “DATA MONITOR” mode with CONSULT-III.

3. Check “A/F SEN1 (B1)” or “A/F SEN1 (B2)” indication.

If the indication is constantly approx. 0 V, go to 

EC-142, "Diagnosis Procedure"

.

If the indication is not constantly approx. 0 V, go to next step.

4. Turn ignition switch OFF, wait at least 10 seconds and then restart engine.

5. Drive and accelerate vehicle to more than 40 km/h (25 MPH) within 20 seconds after restarting engine.

PBIB3353E

PBIB3354E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible Cause

P0131
0131
(Bank 1)

Air fuel ratio (A/F) sensor 1 
circuit low voltage

• The A/F signal computed by ECM from the A/

F sensor 1 signal is constantly approx. 0V.

• Harness or connectors

(The A/F sensor 1 circuit is open or 
shorted.)

• Air fuel ratio (A/F) sensor 1

P0151
0151
(Bank 2)

EC-142

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P0131, P0151 A/F SENSOR 1

6. Maintain the following conditions for about 20 consecutive seconds.

NOTE:

• Keep the accelerator pedal as steady as possible during the cruising.

• If this procedure is not completed within 1 minute after restarting engine at step 4, return to step

4.

7. Check 1st trip DTC.

8. If 1st trip DTC is displayed, go to 

EC-142, "Diagnosis Procedure"

.

WITH GST

Follow the procedure “WITH CONSULT-III” above.

Diagnosis Procedure

INFOID:0000000005149163

1.

CHECK GROUND CONNECTIONS

1. Turn ignition switch OFF.

2. Loosen and retighten three ground screws on the body.

Refer to 

EC-85, "Ground Inspection"

.

OK or NG

OK

>> GO TO 2.

NG

>> Repair or replace ground connections.

2.

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

1. Disconnect A/F sensor 1 harness connector.

2. Turn ignition switch ON.

ENG SPEED

1,000 - 3,200 rpm

VHCL SPEED SE

More than 40 km/h (25 MPH)

B/FUEL SCHDL

1.5 - 9.0 msec

Gear position

Suitable position

BBIA0354E

BBIA0376E

P0131, P0151 A/F SENSOR 1

EC-143

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3. Check voltage between A/F sensor 1 terminal 4 and ground with

CONSULT-III or tester.

OK or NG

OK

>> GO TO 4.

NG

>> GO TO 3.

3.

DETECT MALFUNCTIONING PART

Check the following.

• Harness connectors E5, F14

• IPDM E/R harness connector E119

• 15A fuse (No. 54)

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

>> Repair or replace harness or connectors.

4.

CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1. Turn ignition switch OFF.

2. Disconnect ECM harness connector.

3. Check harness continuity between A/F sensor 1 terminal and ECM terminal as follows.

Refer to Wiring Diagram.

4. Check harness continuity between the following terminals and ground.

Refer to Wiring Diagram.

5. Also check harness for 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.

5.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-35, "How to Check Terminal"

 and 

GI-38, "Intermittent Incident"

.

OK or NG

OK

>> GO TO 6.

NG

>> Repair or replace.

Voltage: Battery voltage

PBIB3308E

A/F sensor 1 terminal

ECM terminal

Bank1

1

35

2

56

Bank 2

1

16

2

75

Continuity should exist.

Bank 1

Bank 2

A/F sensor 1 terminal

ECM terminal

A/F sensor 1 terminal

ECM terminal

1

35

1

16

2

56

2

75

Continuity should not exist.