초록

A method of sensing and determining open circuits and short circuits to the solenoid-actuated valves for the electronic automatic transmission.

대표청구항 ▼

In a vehicle having an engine and a transmission system including an input member, an output member, a torque converter assembly for transmitting torque between the engine and the input member, a gear assembly for changing the ratio of torque between the input member and output member, a plurality o

In a vehicle having an engine and a transmission system including an input member, an output member, a torque converter assembly for transmitting torque between the engine and the input member, a gear assembly for changing the ratio of torque between the input member and output member, a plurality of friction elements for shifting the gear assembly, a fluid actuating device being movable for applying at least one friction element, at least one solenoid-actuated valve being movable in response to the presence or absence of electrical power to the valve for directing fluid flow between a fluid source and the fluid actuating device, sensors providing signal indicative of measurement data for predetermined conditions, a controller having a communications port and memory for processing and storing the signals and predetermined values and providing signals to control the solenoid-actuated valves, a method of testing diagnostically a plurality of sensors which indicate the position of a shift lever for a predetermined operating mode of the transmission, said method comprising the steps of: checking whether a new command was received from a communications port of the controller; retrieving shift lever position information from the sensors; outputting the retrieved shift lever position information to the communications port; comparing the retrieved shift lever position information to previous shift lever position information and updating a flag if the compared information of the positions are not equal; setting a flag to indicate the retrieved shift lever position information; checking for a predetermined flag if a command was received from the communications port; setting a predetermined flag based on the type of checked predetermined flag; and outputting the predetermined flags that were set.