Nissan Altima 2007-2012 Service Manual: Lock-up and select control system

System Diagram

System Description

• The torque converter clutch piston in the torque converter is engaged to eliminate torque converter slip to increase power transmission efficiency.

• The torque converter clutch control valve operation is controlled by the torque converter clutch solenoid valve, which is controlled by a signal from TCM. The torque converter clutch control valve engages or releases the torque converter clutch piston.

• When shifting between “N” (“P”) ⇔ “D” (“R”), torque converter clutch solenoid controls engagement power of forward clutch and reverse brake.

• The lock-up applied gear range was expanded by locking up the torque converter at a lower vehicle speed than conventional CVT models.

TORQUE CONVERTER CLUTCH AND SELECT CONTROL VALVE CONTROL

Lock-up Released

In the lock-up released state, the torque converter clutch control valve is set into the unlocked state by the torque converter clutch solenoid and the lock-up apply pressure is drained.

In this way, the torque converter clutch piston is not coupled.

Lock-up Applied

In the lock-up applied state, the torque converter clutch control valve is set into the locked state by the torque converter clutch solenoid and lock-up apply pressure is generated.

In this way, the torque converter clutch piston is pressed and coupled.

Select Control

When shifting between “N” (“P”) ⇔ “D” (“R”), optimize the operating pressure on the basis of the throttle position, the engine speed, and the secondary pulley (output) revolution speed to lessen the shift shock.

Component Parts Location - Coupe

1. Control device assembly (Manual mode select switch and manual mode position select switch)

2. Accelerator pedal position (APP) sensor

3. Secondary speed sensor

4. CVT unit harness connector

5. TCM

6. Battery

7. Shift position indicator Manual mode indicator

Component Parts Location - Sedan

1. Control device assembly (Manual mode select switch and manual mode position select switch)

2. Accelerator pedal position (APP) sensor

3. Secondary speed sensor

4. CVT unit harness connector

5. TCM

6. Battery

7. Shift position indicator Manual mode indicator

Component Description

TRANSAXLE ASSEMBLY

EXCEPT TRANSAXLE ASSEMBLY

    Control system
    System Diagram System Description The CVT senses vehicle operating conditions through various sensors. It always controls the optimum shift position and reduces shifting and lock-up shocks. C ...

    Shift mechanism
    System Diagram NOTE: The gear ratio is set for every position separately. System Description In order to select the gear ratio which can obtain the driving force in accordance with driver's i ...

    Other materials:

    Front regulator
    Exploded View 1. Door 2. Inside seal 3. Door glass 4. Regulator assembly 5. Door module assembly 6. Window motor 7. Cover Removal and Installation REMOVAL 1. Remove the front door finisher. For Sedan Refer to INT-34, "Removal and Installation". For Coupe Refer to INT-12, &q ...

    P0102, P0103 maf sensor
    Description The mass air flow sensor (1) is placed in the stream of intake air. It measures the intake flow rate by measuring a part of the entire intake flow. The mass air flow sensor controls the temperature of the hot wire to a certain amount. The heat generated by the hot wire is reduced a ...

    Diagnosis system (BCM)
    COMMON ITEM Diagnosis Description CONSULT-III performs the following functions via CAN communication with BCM. SYSTEM APPLICATION BCM can perform the following functions for each system. NOTE: It can perform the diagnosis modes except the following for all sub system selection items. ...