Nissan Qashqai (2007-2010). Manual — part 420

HO2S2 HEATER

EC-1199

< COMPONENT DIAGNOSIS >

[MR20DE (WITHOUT EURO-OBD)]

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HO2S2 HEATER

Description

INFOID:0000000001102129

SYSTEM DESCRIPTION

The ECM performs ON/OFF control of the heated oxygen sensor 2 heater corresponding to the engine speed,
amount of intake air and engine coolant temperature.

OPERATION

Component Function Check

INFOID:0000000001102130

1.

CHECK HEATED OXYGEN SENSOR 2 HRATER FUNCTION

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 engine and let it idle.

4.

Check the voltage between ECM harness connector and ground under the following condition.

: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Go to

EC-1196, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000001102131

1.

CHECK GROUND CONNECTION

1.

Turn ignition switch OFF.

2.

Check ground connection E21. Refer to Ground Inspection in

GI-41, "Circuit Inspection"

.

Is the inspection result normal?

YES

>> GO TO 2.

Sensor

Input signal to ECM

ECM function

Actuator

Camshaft position sensor (PHASE)
Crankshaft position sensor (POS)

Engine speed

Heated oxygen sensor 2
heater control

Heated oxygen sensor 2 heater

Engine coolant temperature sensor

Engine coolant temperature

Mass air flow sensor

Amount of intake air

Engine speed rpm

Heated oxygen sensor 2 heater

Above 3,900

OFF

Below 3,900 rpm after the following conditions are met.
• Engine: After warming up
• Keeping the engine speed between 3,500 and 4,000 rpm for 1

minute and at idle for 1 minute under no load

ON

ECM

Ground

Condition

Voltage signal

Connector

Terminal

F7

5

[HO2S2 heater signal]

Ground

At idle

Approx. 10V

Engine speed: Above 3,600 rpm

BATTERY VOLTAGE

(11 - 14V)

JMBIA0325GB

EC-1200

< COMPONENT DIAGNOSIS >

[MR20DE (WITHOUT EURO-OBD)]

HO2S2 HEATER

NO

>> Repair or replace ground connection.

2.

CHECK HO2S2 POWER SUPPLY CIRCUIT

1.

Disconnect HO2S2 harness connector.

2.

Turn ignition switch ON.

3.

Check the voltage between HO2S2 harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> GO TO 3.

3.

DETECT MALFUNCTIONING PART

Check the following.
• IPDM E/R connector E11
• 10A fuse (No. 63)
• Harness for open or short between heated oxygen sensor 2 and fuse

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

4.

CHECK HO2S2 OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.

Turn ignition switch OFF.

2.

Disconnect ECM harness connector.

3.

Check the continuity between HO2S2 harness connector and ECM harness connector.

4.

Also check harness for short to ground and 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 F121, E7
• Harness for open or short between heated oxygen sensor 2 and ECM

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

6.

CHECK HO2S2 HEATER

Refer to

EC-1205, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 8.

NO

>> GO TO 7.

7.

REPLACE HEATED OXYGEN SENSOR 2

Replace heated oxygen sensor 2.

CAUTION:

• Discard any heated oxygen 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 oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread

Cleaner tool and approved anti-seize lubricant.

HO2S2

Ground

Voltage

Connector

Terminal

E58

2

Ground

Battery voltage

HO2S2

ECM

Continuity

Connector

Terminal

Connector

Terminal

E58

3

F7

5

Existed

HO2S2 HEATER

EC-1201

< COMPONENT DIAGNOSIS >

[MR20DE (WITHOUT EURO-OBD)]

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>> INSPECTION END

8.

CHECK INTERMITTENT INCIDENT

Refer to

GI-39, "Intermittent Incident"

.

>> INSPECTION END

Component Inspection

INFOID:0000000001102132

1.

CHECK HEATED OXYGEN SENSOR 2 HEATER

1.

Turn ignition switch OFF.

2.

Disconnect heated oxygen sensor 2 harness connector.

3.

Check resistance between HO2S2 terminals as follows.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> GO TO 2.

2.

REPLACE HEATED OXYGEN SENSOR 2

Replace heated oxygen sensor 2.

CAUTION:

• Discard any heated oxygen 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 oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread

Cleaner tool and approved anti-seize lubricant.

>> INSPECTION END

Terminals

Resistance [at 25

°

C (77

°

F)]

2 and 3

3.3 - 4.4

Ω

1 and 2, 3, 4

∞

Ω

(Continuity should not exist)

4 and 1, 2, 3

EC-1202

< COMPONENT DIAGNOSIS >

[MR20DE (WITHOUT EURO-OBD)]

IAT SENSOR

IAT SENSOR

Description

INFOID:0000000001102133

The intake air temperature sensor is built-into mass air flow sensor
(1). The sensor detects intake air temperature and transmits a signal
to the ECM.
The temperature sensing unit uses a thermistor which is sensitive to
the change in temperature. Electrical resistance of the thermistor
decreases in response to the temperature rise.

<Reference data>

*: These data are reference values and are measured between ECM terminal 50
(Intake air temperature sensor) and ground.

CAUTION:

Do not use ECM ground terminals when measuring input/output voltage. Doing
so may result in damage to the ECM's transistor. Use a ground other than ECM
terminals, such as the ground.

Component Function Check

INFOID:0000000001102134

1.

CHECK INTAKE AIR TEMPERATURE SENSOR FUNCTION

1.

Turn ignition switch ON.

2.

Check the voltage between ECM harness connector and ground.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Go to

EC-1206, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000001102135

1.

CHECK GROUND CONNECTION

1.

Turn ignition switch OFF.

2.

Check ground connection E21. Refer to Ground Inspection in

GI-41, "Circuit Inspection"

.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair or replace ground connection.

2.

CHECK INTAKE AIR TEMPERATURE SENSOR POWER SUPPLY CIRCUIT

1.

Disconnect mass air flow sensor (with intake air temperature sensor) harness connector.

2.

Turn ignition switch ON.

3.

Check the voltage between mass air flow sensor harness connector and ground.

PBIA9559J

Intake air temperature

°

C (

°

F)

Voltage*

V

Resistance

k

Ω

25 (77)

3.3

1.800 - 2.200

80 (176)

1.2

0.283 - 0.359

SEF012P

ECM

Ground

Voltage

Connector

Terminal

F8

46

Ground

Approx. 0 - 4.8V