Patent ID: 6056669
Filing Date: 2000-05-02
Classification: F16H,Y10S,Y10T

Abstract:
A push-button range control system for an automotive vehicle driveline having a throttle-controlled engine and a multiple ratio transmission;servo actuator means for shifting torque transmitting elements of said transmission to effect speed ratio changes;a hydraulic pressure source for said actuator means;valve control means for distributing actuating pressure to said actuator means to effect a drive range mode, a neutral mode, and a reverse drive mode;electronic controller means responsive to operating variables of said engine and said transmission for effecting speed ratio changes in said drive range mode;a push-button driver interface means communicating with said controller means and including discrete switches for establishing command signals for said controller means to effect selectively each of said modes;each of said switches having three switch contacts connected to said controller means and multiple signal return grounds, each switch contact corresponding to a separate bit of a three-bit code;said controller means including a memory having first memory registers for storing valid codes and second memory registers for storing error codes indicating and identifying failures in said switches, each error code corresponding to a separate switch failure; andmeans for developing a warning signal in response to the presence of one of said error codes.