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
2. Accelerator pedal position sensor
3. CVT unit harness connector
4. Primary speed sensor
5. Secondary speed sensor
6. PNP switch
7. TCM
8. Battery
9. Shift position indicator Manual mode indicator
Component Parts Location - Sedan
1. Control device assembly
2. Accelerator pedal position sensor
3. CVT unit harness connector
4. Primary speed sensor
5. Secondary speed sensor
6. PNP switch
7. TCM
8. Battery
9. 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.
T ...
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 ...
Other materials:
Reporting safety defects
For USA
If you believe that your vehicle has a defect
which could cause a crash or could
cause injury or death, you should immediately
inform the National Highway Traffic
Safety Administration (NHTSA) in addition
to notifying NISSAN.
If NHTSA receives similar complaints, it
may open an inv ...
On board diagnostic (OBD) system
Trouble Diagnosis Introduction
CAUTION:
• Do not use electrical test equipment on any circuit related to the SRS unless
instructed to do so in
this Service Manual. SRS wiring harnesses can be identified by yellow and/or
orange harness connectors.
• Do not attempt to repair, splice or m ...
Can communication circuit
Diagnosis Procedure
INSPECTION PROCEDURE
1.CONNECTOR INSPECTION
1. Turn the ignition switch OFF.
2. Disconnect the battery cable from the negative terminal.
3. Disconnect all the unit connectors on CAN communication system.
4. Check terminals and connectors for damage, bend and loose con ...