Patent ID: 9593769
Date: 2017-03-14
CPC Classifications: F16H

Claim:
1. A method for detecting an operational error in a converter used as a start-up element in a drive train, wherein the drive train includes a drive unit, a converter, an automatic transmission, a transmission control device, and an output, the method comprising: starting the drive unit, and immediately after start of the drive unit monitoring rotational speed of a turbine of the converter with the transmission control device; with the transmission control device, determining whether, within a defined first time frame after the start of the drive unit, the rotational speed of the turbine reaches or exceeds a first threshold value; the transmission control device inferring a properly filled converter if the rotational speed of the turbine reaches or exceeds the first threshold value within the first time frame; the transmission control device inferring an improperly filled or empty converter if the rotational speed of the turbine does not reach or exceed the first threshold value; via a transmission selector lever, placing the automatic transmission in a shift position; if a properly filled converter is inferred by the transmission control device, further determining whether the rotational speed of the turbine subsequently falls short of a second threshold value for the selected shift position of the automatic transmission within a defined second time frame; and if the rotational speed of the turbine falls short of the second threshold value, the transmission control device infers a frictional connection error in the automatic transmission.