Tony Scott -- Suicide Note Does NOT Reveal Motive

Tony Scott did not explain why he decided to take his own life in the suicide note he left for loved ones ... but did offer a final emotional farewell ... TMZ has learned.

Sources familiar with the investigation tell TMZ ... the note was "short and sweet." Tony said in the note he loved his wife and his 2 kids -- Max and Frank.

We're told Scott's wife has not told investigators about anything that might have triggered a suicide, although as we first reported she did tell investigators Scott did NOT have brain cancer or any other significant medical problem.