This bulletin applies to 2015-2019 GMC Canyon trucks equipped with a MYD automatic transmission. The customer may comment that they hear a high-pitched tone or whine noise with the key on and engine off, or for up to one minute after the engine is shut off.
The noise is heard from outside the vehicle or with a window open. It will be most noticeable in an enclosed area (garage, etc.).
The whine noise may be caused by the internal transmission solenoids being commanded to minimum line pressure by the TCM (transmission control module). Inform the customer that this noise should be considered as a normal operating characteristic and no repairs should be attempted.