Nissan Altima L32. Manual - part 282

P0146 HO2S3

EC-249

< COMPONENT DIAGNOSIS >

[QR25DE FOR CALIFORNIA]

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P0146 HO2S3

Description

INFOID:0000000004349289

The heated oxygen sensor 3, after HC adsorption catalyst (Under

floor), monitors the oxygen level in the exhaust gas on each bank.

This sensor is made of ceramic zirconia. The zirconia generates volt-

age from approximately 1V in richer conditions to 0V in leaner condi-

tions.

Under normal conditions the heated oxygen sensor 3 is not used for

engine control operation.

DTC Logic

INFOID:0000000004349290

DTC DETECTION LOGIC

The heated oxygen sensor 3 has a much longer switching time

between rich and lean than the air fuel ratio (A/F) sensor 1. The oxy-

gen storage capacity of the three way catalyst (manifold) causes the

longer switching time. To judge the malfunctions of heated oxygen

sensor 3, ECM monitors whether the voltage is unusually high during

the various driving condition such as fuel-cut.

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at

least 10 seconds before conducting the next test.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE

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

2. Repeat the following procedure 3 times.

-

Drive vehicle at a speed of 80 km/h (50 MPH) or more for at least 3 consecutive minutes.

CAUTION:

Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws.

NOTE:

•

Keep the vehicle speed as steady as possible during the cruising.

•

Never raise engine sped above 3,600 rpm in this step.

-

Release accelerator pedal fully and stop vehicle with engine running.

NOTE:

Never turn ignition switch OFF.

3. Check 1st trip DTC.
Is 1st trip DTC detected?

YES

>> Go to 

EC-250, "Diagnosis Procedure"

.

NO

>> INSPECTION END

SEF327R

PBIB1848E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P0146

Heated oxygen sensor 3 
circuit no activity detect-
ed

An excessively high voltage from the sensor is 
sent to ECM.

• Harness or connectors

(The sensor circuit is open or shorted)

• Heated oxygen sensor 3

EC-250

< COMPONENT DIAGNOSIS >

[QR25DE FOR CALIFORNIA]

P0146 HO2S3

Diagnosis Procedure

INFOID:0000000004349291

1.

CHECK GROUND CONNECTION

1. Turn ignition switch OFF.

2. Check ground connection E9. Refer to Ground Inspection in 

GI-45, "Circuit Inspection"

.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair or replace ground connection.

2.

CHECK HO2S3 GROUND CIRCUIT FOR OPEN AND SHORT

1. Turn ignition switch OFF.

2. Disconnect heated oxygen sensor 3 harness connector.

3. Disconnect ECM harness connector.

4. Check the continuity between HO2S3 harness connector and ECM harness connector.

5. Also check harness for short to ground and short to power.
Is the inspection result normal?

YES

>> GO TO 4.

NO

>> GO TO 3.

3.

DETECT MALFUNCTIONING PART

Check the following.

• Harness connectors F58, F101

• Harness for open or short between heated oxygen sensor 3 and ECM

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

4.

CHECK HO2S3 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1. Check the continuity between HO2S3 harness connector and ECM harness connector.

2. Check the continuity between HO2S3 harness connector or ECM harness connector and ground.

3. Also check harness for short to power.
Is the inspection result normal?

YES

>> GO TO 6.

NO

>> GO TO 5.

5.

DETECT MALFUNCTIONING PART

Check the following.

• Harness connectors F58, F101

• Harness for open or short between heated oxygen sensor 3 and ECM

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

HO2S3

ECM

Continuity

Connector

Terminal

Connector

Terminal

F102

1

F13

35

Existed

HO2S3

ECM

Continuity

Connector

Terminal

Connector

Terminal

F102

4

F13

34

Existed

HO2S3

ECM

Ground

Continuity

Connector

Terminal

Connector

Terminal

F102

4

F13

34

Ground

Not existed

P0146 HO2S3

EC-251

< COMPONENT DIAGNOSIS >

[QR25DE FOR CALIFORNIA]

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6.

CHECK HO2S3 CONNECTOR FOR WATER

Check connectors for water.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Repair or replace harness or connectors.

7.

CHECK HEATED OXYGEN SENSOR 3

Refer to 

EC-251, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> GO TO 8.

8.

REPLACE HEATED OXYGEN SENSOR 3

Replace heated oxygen sensor 3.

CAUTION:

• Discard any 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 sensor, clean exhaust system threads using oxygen sensor thread cleaner

[commercial service tool (J-43897-18 or J-43897-12)] and approved anti-seize lubricant (commercial

service tool).

>> INSPECTION END

9.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-42, "Intermittent Incident"

.

>> INSPECTION END

Component Inspection

INFOID:0000000004349292

1.

INSPECTION START

Do you have CONSULT-III?
Do you have CONSULT-III?

YES

>> GO TO 2.

NO

>> GO TO 3.

2.

CHECK HEATED OXYGEN SENSOR 3

With CONSULT-III

CAUTION:

Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws.

1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-III.

2. Start engine and warm it up to the normal operating temperature.

3. Turn ignition switch OFF and wait at least 10 seconds.

4. Start the engine and drive vehicle at a speed of 80 km/h (50 MPH) or more for at least 3 consecutive min-

utes.

NOTE:

Keep the vehicle speed as steady as possible during the cruising.

5. Select “FUEL INJECTION” in “ACTIVE TEST” mode, and select “HO2S3 (B1)” as the monitor item with

CONSULT-III.

Water should not exist.

EC-252

< COMPONENT DIAGNOSIS >

[QR25DE FOR CALIFORNIA]

P0146 HO2S3

6. Check “HO2S3 (B1)” at idle speed when adjusting “FUEL INJECTION” to 

±25%.

“HO2S3 (B1)” should be above 0.68V at least once when the “FUEL INJECTION” is +25%.

“HO2S3 (B1)” should be below 0.18V at least once when the “FUEL INJECTION” is 

−25%.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> GO TO 6.

3.

CHECK HEATED OXYGEN SENSOR 3-I

Without CONSULT-III

CAUTION:

Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws.

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

2. Turn ignition switch OFF and wait at least 10 seconds.

3. Start the engine and drive vehicle at a speed of 80 km/h (50 MPH) or more for at least 3 consecutive min-

utes.

NOTE:

Keep the vehicle speed as steady as possible during the cruising.

4. Check the voltage between ECM harness connector and ground

under the following condition.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> GO TO 4.

4.

CHECK HEATED OXYGEN SENSOR 3-II

1. Keep vehicle at idling for 10 minutes.

2. Check the voltage between ECM harness connector and ground

under the following condition.

Is the inspection result normal?

YES

>> INSPECTION END

PBIB3458E

ECM

Groun

d

Condition

Voltage

Connec-

tor

Terminal

F13

34

(HO2S3 

signal)

Groun

d

Revving up to 
4,000 rpm un-
der no load at 
least 10 times

The voltage should be above 
0.68 V at least once during this 
procedure.
The voltage should be below 
0.18 V at least once during this 
procedure.

JMBIA1589ZZ

ECM

Ground

Condition

Voltage

Connector

Terminal

F13

34

(HO2S3 

signal)

Ground

Revving up to 
4,000 rpm un-
der no load at 
least 10 times

The voltage should be above 
0.68 V at least once during this 
procedure.
The voltage should be below 
0.18 V at least once during this 
procedure.

JMBIA1589ZZ