Nissan Quest E52. Manual - part 1216

TM-94

< DTC/CIRCUIT DIAGNOSIS >

[CVT: RE0F09B]

P0744 TORQUE CONVERTER

P0744 TORQUE CONVERTER

Description

INFOID:0000000009650150

This malfunction is detected when the torque converter clutch does not lock-up as instructed by the TCM. This
is not only caused by electrical malfunctions (circuits open or shorted), but also by mechanical malfunctions
such as control valve sticking, improper solenoid valve operation, etc.

DTC Logic

INFOID:0000000009650151

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

CAUTION:

Always drive vehicle at a safe speed.

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.

CHECK DTC DETECTION

With CONSULT

1.

Start the engine.

2.

Warm up the engine. [Set the CVT fluid to 20

°

C (68

°

F) or more.]

NOTE:
When the ambient temperature is 20

°

C (68

°

F), the CVT fluid usually increases to 50 to 80

°

C (122 to

176

°

F) with driving in an urban area for approximately 10 minutes.

3.

Maintain the following condition for at least 30 seconds.

With GST

Follow the procedure “With CONSULT”.
Is “P0744” detected?

YES

>> Go to 

TM-94, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000009650152

1.

CHECK LINE PRESSURE

Perform line pressure test. Refer to 

TM-65, "Work Procedure"

.

Is the inspection result normal?

YES

>> GO TO 2.

DTC

Trouble diagnosis name

DTC detection condition

Possible cause

P0744

Torque Converter Clutch 
Circuit Intermittent

When below diagnosis conditions are met, torque con-
verter slip speed keeps above the defined value (40 rpm 
+ vehicle speed/2) for 30 seconds or more
• Diagnosis Conditions
- Selector lever: “D” position
- Vehicle speed: 11 km/h (7 MPH) or more
- Accelerator pedal position: 1.1/8 or more
- Engine speed: 450 rpm or more
- CVT fluid temperature: 20

°

C – 180

°

C (68

°

F – 356

°

F)

- LU command pressure: More than 0.2 MPa

• Torque converter clutch solenoid 

valve

• Hydraulic control circuit

Selector lever

: “D” position 

Accelerator pedal position

: 1.1/8 or more

Vehicle speed

: 25 km/h (16 MPH) or more

P0744 TORQUE CONVERTER

TM-95

< DTC/CIRCUIT DIAGNOSIS >

[CVT: RE0F09B]

C

E

F

G

H

I

J

K

L

M

A

B

TM

N

O

P

NO

>> Repair or replace damaged parts. Refer to 

TM-65, "Work Procedure"

.

2.

CHECK TORQUE CONVERTER CLUTCH SOLENOID VALVE

Check torque converter clutch solenoid valve. Refer to 

TM-92, "Diagnosis Procedure"

.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> GO TO 6.

3.

CHECK LOCK-UP SELECT SOLENOID VALVE

Check lock-up select solenoid valve. Refer to 

TM-123, "Diagnosis Procedure"

.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair or replace damaged parts.

4.

CHECK PRIMARY SPEED SENSOR SYSTEM

Check primary speed sensor system. Refer to 

TM-86, "Diagnosis Procedure"

.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Repair or replace damaged parts.

5.

CHECK SECONDARY SPEED SENSOR SYSTEM

Check secondary speed sensor system. Refer to 

TM-88, "Diagnosis Procedure"

.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Repair or replace damaged parts.

6.

CHECK DTC

With CONSULT

1.

Perform “DTC CONFIRMATION PROCEDURE”. Refer to 

TM-94, "DTC Logic"

.

2.

Check DTC.

Is “P0744” displayed?

YES

>> Replace the transaxle assembly due to malfunction in the torque converter clutch solenoid valve.

Refer to 

TM-174, "Removal and Installation"

.

NO

>> Check intermittent incident. Refer to 

GI-42, "Intermittent Incident"

.

TM-96

< DTC/CIRCUIT DIAGNOSIS >

[CVT: RE0F09B]

P0745 PRESSURE CONTROL SOLENOID A

P0745 PRESSURE CONTROL SOLENOID A

DTC Logic

INFOID:0000000009650153

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

CAUTION:

Always drive vehicle at a safe speed.

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.

CHECK DTC DETECTION

With CONSULT

1.

Start the engine.

2.

Drive the vehicle at least for 10 seconds.

3.

Stop the vehicle.

4.

Check DTC.

With GST

Follow the procedure “With CONSULT”.

Is “P0745” detected?

YES

>> Go to 

TM-96, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000009650154

1.

CHECK LINE PRESSURE SOLENOID VALVE

1.

Disconnect the CVT unit connector.

2.

Check the line pressure solenoid valve. Refer to 

TM-97, "Component Inspection (Line Pressure Solenoid

Valve)"

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Replace the transaxle assembly due to malfunction in the line pressure solenoid valve. Refer to

TM-174, "Removal and Installation"

.

2.

CHECK HARNESS BETWEEN TCM AND CVT UNIT

1.

Disconnect the TCM connector.

2.

Check the continuity between TCM harness connector terminal and CVT unit harness connector terminal.

DTC

Trouble diagnosis name

DTC detection condition

Possible cause

P0745

Pressure Control Solenoid “A”

Line pressure solenoid valve monitor voltage 
value of TCM keeps less than 70% of com-
mand voltage for 1 second or more

• Harness or connectors

(Line pressure solenoid valve circuit 
is open or shorted.)

• Line pressure solenoid valve

When below diagnosis conditions are met, line 
pressure solenoid valve monitor current value 
of TCM keeps less than 400 mA for 5 seconds 
or more
• Diagnosis Condition
- Line pressure solenoid valve command cur-

rent value: 750 mA or more

P0745 PRESSURE CONTROL SOLENOID A

TM-97

< DTC/CIRCUIT DIAGNOSIS >

[CVT: RE0F09B]

C

E

F

G

H

I

J

K

L

M

A

B

TM

N

O

P

3.

Check the continuity between TCM harness connector terminal and ground.

Is the inspection result normal?

YES

>> Check intermittent incident. Refer to 

GI-42, "Intermittent Incident"

.

NO

>> Repair or replace damaged parts.

Component Inspection (Line Pressure Solenoid Valve)

INFOID:0000000009650155

1.

CHECK LINE PRESSURE SOLENOID VALVE

Check the resistance between CVT unit connector terminal and ground.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace the transaxle assembly due to malfunction in the line pressure solenoid valve. Refer to

TM-174, "Removal and Installation"

.

TCM

CVT unit

Continuity

Connector

Terminal

Connector

Terminal

F23

40

F24

2

Existed

TCM

—

Continuity

Connector

Terminal

F23

40

Ground

Not existed

CVT unit

—

Condition

Resistance (Approx.)

Terminal

2

Ground

CVT fluid temperature: 20

°

C (68

°

F)

5.60 – 6.60 

Ω

CVT fluid temperature: 50

°

C (122

°

F)

6.76 – 6.87 

Ω

CVT fluid temperature: 80

°

C (176

°

F)

7.47 – 7.59 

Ω