Blinking Drive Indicator Light

Although the transmission shifts smoothly as it always has, the transmission D position indicator light on my 2002 Odyssey blinks most of the time. It sometimes stops when I turn the engine off and restart it. What does this indicate and what should I do about it?

It means there's a fault in the transmission circuit. It should throw a diagnostic code. I know auto zone & advance auto will read engine codes for free.