Ford Global Technolgoies, LLC

Luis Juarez

Adam Krach

Michael Joseph Giunta

Sitaram Rejeti

Vaibhav Khanna

Peter Turpel

Methods and systems are provided for diagnosing a stuck Active Transmission Warmup (ATWU) valve. In one example, a method for an ATWU valve monitoring routine of a vehicle comprises determining a temperature difference between an engine coolant temperature (ECT) and a transmission fluid temperature (TFT) over a duration before the ATWU valve is commanded from a closed position to an open position or from the open position to the closed position comparing a rate of change of the TFT before and after the ATWU valve is commanded to the open position or the closed position; and indicating a stuck ATWU valve based on at least one of the temperature difference, the TFT rate of change comparison, or a combination thereof, based on a calibration parameter.

Systems and methods for diagnosing stuck ATWU valve

Systems and methods for diagnosing operation of a transmission warm-up valve are presented. In one example, the transmission warm-up valve is commanded to an open position and an estimated transmission fluid temperature is compared to an actual transmission fluid temperature to determine whether or not the transmission warm-up valve is operating as commanded.

Growing community of inventors

Northville, MI, United States of America

Luis Juarez