Nissan Titan A60. Manual - part 921

TM-72

< DTC/CIRCUIT DIAGNOSIS >

P0744 TORQUE CONVERTER

P0744 TORQUE CONVERTER

Description

INFOID:0000000006159320

This malfunction is detected when the A/T does not lock-up. This is not only caused by electrical malfunction

(circuits open or shorted) but also by mechanical malfunction such as control valve sticking, improper solenoid

valve operation, etc.

CONSULT-III Reference Value in Data Monitor Mode

INFOID:0000000006159321

On Board Diagnosis Logic

INFOID:0000000006159322

• This is an OBD-II self-diagnostic item.

• Diagnostic trouble code “P0744” with CONSULT-III or 3rd judgment flicker without CONSULT-III is detected

under the following conditions.

- When A/T cannot perform lock-up even if electrical circuit is good.

- When TCM detects as irregular by comparing difference value with slip rotation.

Possible Cause

INFOID:0000000006159323

• Harness or connectors

(The solenoid circuit is open or shorted.)

• Torque converter clutch solenoid valve

• Hydraulic control circuit

DTC Confirmation Procedure

INFOID:0000000006159324

CAUTION:

Always drive vehicle at a safe speed.

NOTE:

If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch “OFF”

and wait at least 10 seconds before performing the next test.

After the repair, perform the following procedure to confirm the malfunction is eliminated.

 WITH CONSULT-III

1. Start engine.

2. Select “DATA MONITOR" mode for "TRANSMISSION" with CONSULT-III.

3. Drive vehicle and maintain the following conditions for at least 30 consecutive seconds. 

ACCELE POSI: More than 1.0/8 

SLCT LVR POSI: “D” position 

TCC SOLENOID: 0.4 - 0.6 A

VEHICLE SPEED: 80 km/h (50 MPH) or more

Driving locations: Driving the vehicle uphill (increased engine load) will help maintain the driving

conditions required for this test.

4. If DTC is detected, go to 

TM-72, "Diagnosis Procedure"

.

 WITH GST

Follow the procedure “With CONSULT-III”.

Diagnosis Procedure

INFOID:0000000006159325

1.

CHECK INPUT SIGNAL

With CONSULT-III

1. Turn ignition switch “ON”. 

2. Select “MAIN SIGNALS” in “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.

3. Start the engine.

Item name

Condition 

Display value (Approx.)

TCC SOLENOID

When performing slip lock-up

0.2 - 0.4 A

When performing lock-up

0.4 - 0.6 A

P0744 TORQUE CONVERTER

TM-73

< DTC/CIRCUIT DIAGNOSIS >

C

E

F

G

H

I

J

K

L

M

A

B

TM

N

O

P

4. Read out the value of “TCC SOLENOID” while driving.

OK or NG

OK

>> GO TO 4.

NG

>> GO TO 2.

2.

CHECK TCM POWER SUPPLY AND GROUND CIRCUIT

Check TCM power supply and ground circuit. Refer to 

TM-101, "Diagnosis Procedure"

.

OK or NG

OK

>> GO TO 3.

NG

>> Repair or replace damaged parts.

3.

DETECT MALFUNCTIONING ITEM

Check the following items:

• The A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG

OK

>> Replace the control valve with TCM. Refer to 

TM-197, "Control Valve with TCM"

.

NG

>> Repair or replace damaged parts.

4.

CHECK DTC

Perform “DTC Confirmation Procedure”.

• Refer to 

TM-72, "DTC Confirmation Procedure"

.

OK or NG

OK

>> INSPECTION END

NG

>> GO TO 2.

Item name

Condition 

Display value (Approx.)

TCC SOLENOID

When performing slip lock-up

0.2 - 0.4 A

When performing lock-up

0.4 - 0.6 A

TM-74

< DTC/CIRCUIT DIAGNOSIS >

P0745 PRESSURE CONTROL SOLENOID A

P0745 PRESSURE CONTROL SOLENOID A

Description

INFOID:0000000006159326

The line pressure solenoid valve regulates the oil pump discharge pressure to suit the driving condition in

response to a signal sent from the TCM.

CONSULT-III Reference Value in Data Monitor Mode

INFOID:0000000006159327

On Board Diagnosis Logic

INFOID:0000000006159328

• This is an OBD-II self-diagnostic item.

• Diagnostic trouble code “P0745” with CONSULT-III or 4th judgment flicker without CONSULT-III is detected

under the following conditions.

- When TCM detects an improper voltage drop when it tries to operate the solenoid valve.

- When TCM detects as irregular by comparing target value with monitor value.

Possible Cause

INFOID:0000000006159329

• Harness or connectors

(The solenoid circuit is open or shorted.)

• Line pressure solenoid valve

DTC Confirmation Procedure

INFOID:0000000006159330

NOTE:

If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch “OFF”

and wait at least 10 seconds before performing the next test.

After the repair, perform the following procedure to confirm the malfunction is eliminated.

 WITH CONSULT-III

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

2. Engine start and wait at least 5 second.

3.  If DTC is detected, go to 

TM-74, "Diagnosis Procedure"

.

 WITH GST

Follow the procedure “With CONSULT-III”.

Diagnosis Procedure

INFOID:0000000006159331

1.

CHECK INPUT SIGNAL

With CONSULT-III

1. Turn ignition switch “ON”.

2. Select “MAIN SIGNALS” in “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.

3. Start the engine.

4. Read out the value of “LINE PRES SOL” while driving.

OK or NG

OK

>> GO TO 4.

NG

>> GO TO 2.

2.

CHECK TCM POWER SUPPLY AND GROUND CIRCUIT

Check TCM power supply and ground circuit. Refer to 

TM-101, "Diagnosis Procedure"

.

Item name

Condition 

Display value (Approx.)

LINE PRES SOL

During driving

0.2 - 0.6 A

Item name

Condition 

Display value (Approx.) 

LINE PRES SOL

During driving

0.2 - 0.6 A

P0745 PRESSURE CONTROL SOLENOID A

TM-75

< DTC/CIRCUIT DIAGNOSIS >

C

E

F

G

H

I

J

K

L

M

A

B

TM

N

O

P

OK or NG

OK

>> GO TO 3.

NG

>> Repair or replace damaged parts.

3.

DETECT MALFUNCTIONING ITEM

Check the following items:

• The A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG

OK

>> Replace the control valve with TCM. Refer to 

TM-197, "Control Valve with TCM"

.

NG

>> Repair or replace damaged parts.

4.

CHECK DTC

Perform “DTC Confirmation Procedure”.

• Refer to 

TM-74, "DTC Confirmation Procedure"

.

OK or NG

OK

>> INSPECTION END

NG

>> GO TO 2.