"O/D off" light flashing
 

I have a 2000 grand Marquis and the "O/D off" light on the dashboard started flashing. It flashed until I killed the engine and let the car sit for about fifteen minutes and when I restarted it, it was off. What should I look for?
Thanks!

Look in the owners manual to see what it might mean. I'm assuming the car sensed a problem in the transmission, such as unexpected ratio between engine rpms and driveshaft rmps.

My girlfriend's car would do the same thing because her speedometer cable was broken and the computer sensed the difference.