Datsun/ Nissan refers to their cruise control as the Automatic Speed Control Device (ASCD) system. The ASCD system maintains a desired speed of the vehicle under normal driving conditions. The cruise control system's main parts are the control switches, control unit, actuator, speed sensor, vacuum pump, vacuum pump relay, vacuum switch, vacuum tank, electrical release switches and electrical harness.
The use of the speed control is not recommended when driving conditions do not permit maintaining a constant speed, such as in heavy traffic or on roads that are winding, icy, snow covered or slippery.
See Figures 1, 2, 3, 4 and 5