Nissan Qashqai J11. Manual - part 538

EC9-308

< DTC/CIRCUIT DIAGNOSIS >

[R9M]

P1489 LOW PRESSURE EGR VOLUME CONTROL VALVE UPSTREAM TEM-

PERATURE SENSOR

2.

Check low pressure EGR volume control valve circuit for open and short.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair or replace error-detected parts.

4.

CHECK DIESEL PARTICULATE FILTER

Refer to 

EC9-359, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Replace diesel particulate filter.

5.

CHECK LOW PRESSURE EGR VOLUME CONTROL VALVE UPSTREAM TEMPERATURE SENSOR

Refer to 

EC9-308, "Component Inspection (Low Pressure EGR Temperature Sensor)"

.

Is the inspection result normal?

YES

>> Check intermittent incident. Refer to 

GI-41, "Intermittent Incident"

.

NO

>> Replace error-detected parts. 

Component Inspection (Low Pressure EGR Temperature Sensor)

INFOID:0000000010309304

1.

CHECK LOW PRESSURE EGR TEMPERATURE SENSOR

1.

Disconnect low pressure EGR volume control valve upstream temperature sensor harness connector.

2.

Check resistance between low pressure EGR temperature sensor terminals under the following condi-
tions.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace low pressure EGR temperature sensor.

+

-

Continuity

ECM

Low pressure EGR volume 

control valve

Connector

Terminal

Connector

Terminal

F82

55

F77

1

Existed

65

2

69

3

F83

136

6

143

5

Low pressure EGR temperature sen-

sor

Condition

Resistance

+

-

Terminal

2

1

Temperature

°

 C (

°

F)

20 (68)

57.094 – 65.836 k

Ω

P148A HIGH PRESSURE EGR VOLUME CONTROL VALVE

EC9-309

< DTC/CIRCUIT DIAGNOSIS >

[R9M]

C

D

E

F

G

H

I

J

K

L

M

A

EC9

N

P

O

P148A HIGH PRESSURE EGR VOLUME CONTROL VALVE

DTC Logic

INFOID:0000000010499293

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 1 minute before conducting the next test.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE

1.

Start engine and warm it up to normal operation temperature.

2.

Turn ignition switch OFF and wait at least 60 seconds.

3.

Turn ignition switch ON.

4.

Check DTC.

Is DTC detected?

YES

>> Proceed to 

EC9-309, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000010499294

1.

CHECK HIGH PRESSURE EGR VOLUME CONTROL VALVE

Visually check high pressure EGR volume control valve for chipping.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair or replace error-detected parts.

2.

CHECK ECM HARNESS CONNECTOR CONNECTIONS

Check ECM harness connector connection.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Repair or replace error-detected parts.

3.

CHECK EGR VOLUME CONTROL VALVE HARNESS CONNECTOR CONNECTIONS

Check low pressure EGR valve and high pressure EGR valve harness connector connection.
Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair or replace error-detected parts.

4.

CHECK HIGH PRESSURE EGR VOLUME CONTROL VALVE CIRCUIT

1.

Turn ignition switch OFF.

2.

Check EGR valve circuit for open and short.

DTC No.

CONSULT screen terms

(Trouble diagnosis content)

DTC detecting condition

Possible cause

148A

HIGH PRESSURE EGR VALVE 
FUNCTION
(High pressure EGR valve func-
tion)
• 1.DEF: NO RESPONSE 

FROM THE VALVE MOTOR

ECM detects an incorrect position of high Pres-
sure EGR volume control valve.

• Harness or connectors
• High pressure EGR volume control 

valve

• High pressure EGR volume control 

valve volume control valve position 
sensor

EC9-310

< DTC/CIRCUIT DIAGNOSIS >

[R9M]

P148A HIGH PRESSURE EGR VOLUME CONTROL VALVE

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Repair or replace error-detected parts.

5.

DTC CONFIRMATION PROCEDURE

1.

Erase DTC.

2.

Perform DTC confirmation procedure again. Refer to 

EC9-309, "DTC Logic"

.

Is the DTC P148A displayed again?

YES

>> GO TO 6.

NO

>> Check intermittent incident. Refer to 

GI-41, "Intermittent Incident"

.

6.

CHECK HIGH PRESSURE EGR VOLUME CONTROL VALVE MOTOR

Refer to 

ECK-239, "Component Inspection (EGR Volume Control Valve Motor)"

.

Is the inspection result normal?

YES

>> Check intermittent incident. Refer to 

GI-41, "Intermittent Incident"

.

NO

>> Replace high pressure EGR volume control valve.

Component Inspection (High Pressure EGR Volume Control Valve Motor)

INFOID:0000000010499295

1.

CHECK HIGH PRESSURE EGR VOLUME CONTROL VALVE

1.

Turn ignition switch OFF.

2.

Disconnect high pressure EGR volume control valve harness connector.

3.

Check resistance between high pressure EGR volume control valve terminals as follows.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace high pressure EGR volume control valve.

+

-

Continuity

ECM

High pressure EGR volume 

control valve

Connector

Terminal

Connector

Terminal

F83

144

F14

1

Existed

148

2

High pressure EGR volume 

control valve

Condition

Resistance (Approx.)

+

-

Terminal

1

2

Temperature 

°

C (

°

F)

23 (73)

2.4 

Ω

P148B LOW PRESSURE EGR VOLUME CONTROL VALVE

EC9-311

< DTC/CIRCUIT DIAGNOSIS >

[R9M]

C

D

E

F

G

H

I

J

K

L

M

A

EC9

N

P

O

P148B LOW PRESSURE EGR VOLUME CONTROL VALVE

DTC Logic

INFOID:0000000010499298

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 1 minute before conducting the next test.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE

1.

Start engine and warm it up to normal operation temperature.

2.

Turn ignition switch OFF and wait at least 60 seconds.

3.

Turn ignition switch ON.

4.

Check DTC.

Is DTC detected?

YES

>> Proceed to 

EC9-311, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000010499299

1.

CHECK LOW PRESSURE EGR VOLUME CONTROL VALVE

Visually check low pressure EGR volume control valve for chipping.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair or replace error-detected parts.

2.

CHECK DIESEL PARTICULATE FILTER

Refer to 

ECK-359, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Replace diesel particulate filter.

3.

CHECK ECM HARNESS CONNECTOR CONNECTIONS

Check ECM harness connector connection.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair or replace error-detected parts.

4.

CHECK LOW PRESSURE EGR VOLUME CONTROL VALVE HARNESS CONNECTOR CONNECTIONS

Check low pressure EGR volume control valve harness connector connection.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Repair or replace error-detected parts.

DTC No.

CONSULT screen terms

(Trouble diagnosis content)

DTC detecting condition

Possible cause

P148B

LOW PRESSURE EGR 
VALVE FUNCTION
(Low pressure EGR valve 
function)
• 1.DEF: NO RESPONSE 

FROM THE VALVE MOTOR

ECM detects an incorrect position of the low pres-
sure EGR volume control valve.

• Low pressure EGR volume 

control valve clogged

• Low pressure EGR volume 

control valve stuck

• Low pressure EGR volume 

control valve