Nissan automatic transmission overrunning clutch valve
Target
The overrunning clutch valve controls the flow of transmission fluid through the overrunning clutch, which allows the torque converter to disengage from the engine at high speeds to improve power transfer efficiency.
Design
The valve usually consists of the following components:
* Valve Body: The retainer that holds all other valve components in place.
*Piston: The moving component that controls the flow of fluid.
* Spring: Holds the piston in the closed position.
* Solenoid valve: Receives an electrical signal from the automatic transmission control unit and opens and closes the valve.
Operating principle
When the valve is closed, fluid cannot flow through the overrunning clutch, which locks the transformer and motor.
When the solenoid valve is activated, it opens the valve, allowing fluid to circulate through the overrunning clutch. This causes the torque converter to be disconnected from the engine, reducing friction losses and increasing efficiency.
Common faults
* Stuck Valve: The valve can become stuck in the open or closed position, which can cause shifting problems or damage to the torque converter.
* Electrical fault: Failure of the solenoid valve may cause the overrunning clutch valve to malfunction.
* Leaks: Worn or damaged valve seals can cause fluid to leak, reducing the effectiveness of the valve.
Troubleshooting Tips
* Check the electrical connector and wiring for damage or corrosion.
* Measure the resistance of the solenoid valve and compare it with the specified values.
* Check the seals for wear or damage.
*If the valve is faulty, it usually needs to be replaced.