Automatic transmission control system with reset

摘要

A speed range control system setting an automatic transmission at a proper speed range in accordance with throttle opening and vehicle traveling speed. The system detects a sudden fall in the level of a vehicle speed signal under the anomalous conditions such as disconnection of a vehicle speed signal line or slippage of wheels due to emergency braking, and then sets the automatic transmission at a safety speed range. After setting at the safety speed range, the speed range of the automatic transmission is set in accordance with the throttle opening and vehicle traveling speed after counting a predetermined number of vehicle speed signal pulses generated in conjunction with rotation of a drive shaft.