Nissan Altima 2007-2012 Service Manual: P0744 A/T TCC S/V function (lock -up)
Description
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 malfunction (circuits open or shorted), but also by mechanical malfunction such as control valve sticking, improper solenoid valve operation, etc.
DTC Logic
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
CAUTION: Always drive vehicle at a safe speed. NOTE: If “DTC CONFIRMATION PROCEDURE” has been previously performed, always turn ignition switch OFF.
Then wait at least 10 seconds before performing the next test.
1.CHECK DTC DETECTION
1. Turn ignition switch ON.
2. Select “DATA MONITOR”.
3. Start engine and maintain the following condition for at least 30 seconds.
Follow the procedure “With CONSULT-III”.
Is “P0744 A/T TCC S/V FNCTN” detected? YES >> Go to TM-327, "Diagnosis Procedure".
NO >> Check intermittent incident. Refer to GI-42, "Intermittent Incident".
Diagnosis Procedure
1.CHECK LINE PRESSURE
Perform line pressure test. Refer to TM-423, "Inspection and Judgment".
Is the inspection result normal? YES >> GO TO 2.
NO >> Repair or replace damaged parts.
2.CHECK TORQUE CONVERTER CLUTCH SOLENOID VALVE
1. Turn ignition switch OFF.
2. Disconnect CVT unit connector.
3. Check torque converter clutch solenoid valve. Refer to TM-328, "Component Inspection (Torque Converter Clutch Solenoid Valve)".
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace damaged parts.
3.CHECK LOCK-UP SELECT SOLENOID VALVE
Check lock-up select solenoid valve. Refer to TM-328, "Component Inspection (Lock-up Select Solenoid Valve)".
Is the inspection result normal? YES >> GO TO 4.
NO >> Replace transaxle assembly. Refer to TM-447, "Exploded View".
4.CHECK OUTPUT SPEED SENSOR (SECONDARY SPEED SENSOR) SYSTEM
Check output speed sensor (secondary speed sensor) system. Refer to TM-318, "DTC Logic".
Is the inspection result normal? YES >> GO TO 5.
NO >> Repair or replace damaged parts.
5.CHECK INPUT SPEED SENSOR (PRIMARY SPEED SENSOR) SYSTEM
Check input speed sensor (primary speed sensor) system. Refer to TM-313, "DTC Logic".
Is the inspection result normal? YES >> GO TO 6.
NO >> Repair or replace damaged parts.
6.DETECT MALFUNCTIONING ITEMS
Check TCM connector pin terminals for damage or loose connection with harness connector.
Is the inspection result normal? YES >> Replace TCM. Refer to TM-430, "Exploded View".
NO >> Repair or replace damaged parts.
Component Inspection (Torque Converter Clutch Solenoid Valve)
1.CHECK TORQUE CONVERTER CLUTCH SOLENOID VALVE
Check resistance between CVT unit terminal 12 and ground.
Is the inspection result normal? YES >> INSPECTION END
NO >> Perform “SELF-DIAG RESULTS” mode for “TRANSMISSION”.
Component Inspection (Lock-up Select Solenoid Valve)
1.CHECK LOCK-UP SELECT SOLENOID VALVE
Check resistance between CVT unit terminal 13 and ground.
Is the inspection result normal? YES >> INSPECTION END
NO >> Replace transaxle assembly. Refer to TM-447, "Exploded View".
P0740 torque converter clutch solenoid
valve
Description
• The torque converter clutch solenoid valve is activated by the TCM in
response to signals sent from the vehicle
speed and accelerator pedal position sensors. Lock-up piston operat ...
P0745 line pressure solenoid valve
Description
The pressure control solenoid valve A (line pressure solenoid valve)
regulates the oil pump discharge pressure
to suit the driving condition in response to a signal sent from the TCM. ...
Other materials:
Ecu diagnosis
TCM
Reference Value
VALUES ON THE DIAGNOSIS TOOL
TERMINAL LAYOUT
PHYSICAL VALUES
*1: This circuit is not used.
*2: A circuit tester cannot be used to test this item.
Wiring Diagram - CVT CONTROL SYSTEM -
Coupe
Wiring Diagram - CVT CONTROL SYSTEM - Sedan
...
Engine coolant
Changing Engine Coolant
WARNING:
• To avoid being scalded, never change the coolant when the engine is hot.
• Wrap a thick cloth around cap and carefully remove the cap. First, turn the
cap a quarter of a turn to
release built-up pressure. Then push down and turn the cap all the way to
...
Front door speaker
Removal and Installation
REMOVAL
1. Remove the front door finisher. Refer to INT-12, "Removal and
Installation" (coupe) and INT-34, "Removal
and Installation" (sedan).
2. Remove the front door speaker screws (A), then disconnect the
front door speaker connector and remo ...