The manual valve is exactly what the change lever hooks as many as. According to which gear is selected, the manual valve feeds hydraulic circuits that inhibit selected gears. As an illustration, In case the change lever is in third equipment, it feeds a circuit that prevents overdrive from engaging. https://gearboxauto53063.imblogs.net/83803503/5-tips-about-gearbox-auto-you-can-use-today