摘要 |
A fly-by-wire control for a multi-speed vehicle transmission is provided. Electronic and hydraulic components are provided, including trim valve systems that are multiplexed by logic valves. The trim valves and logic valves are self-diagnosing via a plurality of pressure switches. The control enables single and double range shifts among the multiple forward speed ratios, including shifts to and from sixth and higher forward ratios, reverse and neutral. The control also includes a reduced engine load at stop feature. In addition, a power off/limp home feature provides a plurality of failure modes, including a failure mode for sixth and higher forward speed ratios. |