Nissan Altima HL32 Hybrid. Manual - part 288

EC-136

< COMPONENT DIAGNOSIS >

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P0037, P0038 HO2S2 HEATER

• 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

P0043, P0044 HO2S3 HEATER

EC-137

< COMPONENT DIAGNOSIS >

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P0043, P0044 HO2S3 HEATER

Description

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SYSTEM DESCRIPTION

The ECM performs ON/OFF control of the heated oxygen sensor 3 heater corresponding to the engine speed,

amount of intake air and engine coolant temperature. 

OPERATION

DTC Logic

INFOID:0000000004211377

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-

ing the next test.

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 between 10.5V and 16V at

idle.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE

1. Activate “INSPECTION MODE 1” (

HBC-104

) to start engine, and warm up engine to normal operating

temperature.

Sensor

Input signal to ECM

ECM function

Actuator

Camshaft position sensor (PHASE)

Engine speed

Heated oxygen sensor 3 
heater control

Heated oxygen sensor 3 heater

Crankshaft position sensor (POS)

Engine coolant temperature sensor

Engine coolant temperature

Mass air flow sensor

Amount of intake air

Engine speed

Heated oxygen sensor 3 heater

Above 3,600 rpm

OFF

More than 3 minutes after engine stopped.

Below 3,600 rpm after the following conditions are met.
• Engine: After warming up
• Driving for 3 minutes at a speed of 80 km/h (50 MPH) or more

(Keep the vehicle speed as steady as possible during the cruis-
ing.)

ON

DTC No.

Trouble diagnosis 

name

DTC detecting condition

Possible cause

P0043

Heated oxygen 
sensor 3 heater 
control circuit low

The current amperage in the heated oxygen sen-
sor 3 heater circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM 
through the heated oxygen sensor 3 heater.)

• Harness or connectors

(The heated oxygen sensor 3 heater circuit is 
open or shorted.)

• Heated oxygen sensor 3 heater

P0044

Heated oxygen 
sensor 3 heater 
control circuit high

The current amperage in the heated oxygen sen-
sor 3 heater circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM 
through the heated oxygen sensor 3 heater.)

• Harness or connectors

(The heated oxygen sensor 3 heater circuit is 
shorted.)

• Heated oxygen sensor 3 heater

EC-138

< COMPONENT DIAGNOSIS >

[QR25DE]

P0043, P0044 HO2S3 HEATER

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

3. Turn ignition switch ON.

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

5. Turn ignition switch ON (READY).

6. 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.

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

YES

>> Go to 

EC-138, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000004211378

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 POWER SUPPLY CIRCUIT

1. Disconnect heated oxygen sensor 3 harness connector.

2. Turn ignition switch ON.

3. Check the voltage between HO2S3 harness connector and

ground.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> GO TO 3.

3.

DETECT MALFUNCTIONING PART

Check the following.

• Harness connectors F58, F101

• IPDM E/R harness connector F10

• 15A fuse (No. 37)

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

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

4.

CHECK HO2S3 OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1. Turn ignition switch OFF.

2. Disconnect ECM harness connector.

3. Check harness continuity between HO2S3 harness connector and ECM harness connector.

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

HO2S3

Ground

Voltage

Connector

Terminal

F102

2

Ground

Battery voltage

MBIB0186E

HO2S3

ECM

Continuity

Connector

Terminal

Connector

Terminal

F102

3

F14

17

Existed

P0043, P0044 HO2S3 HEATER

EC-139

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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.

6.

CHECK HEATED OXYGEN SENSOR 3

Refer to 

EC-139, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 8.

NO

>> GO TO 7.

7.

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

8.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-42, "Intermittent Incident"

.

>> INSPECTION END

Component Inspection

INFOID:0000000004211379

1.

CHECK HEATED OXYGEN SENSOR 3 HEATER

1. Turn ignition switch OFF.

2. Disconnect heated oxygen sensor 3 harness connector.