I have a 93 SC400 and the O/D Off light is blinking.. I did a search and found a few people with the same problem, but no resolution... also my speedo stopped working (needle not moving at all). It seems the O/D flashing means that the computer has stored an error code. I'm wondering if the speedo not working could be the error it picked up, or if it is definately something wrong with the transmision... Any help is appreciated.

 

I would bet my left nut one or both of your speed sensors are gone.

Unfortunately, I think they are quite pricey.

Your car shifting normally?

 

car seems to drive fine... i did have to floor it on the freeway today on a freeway junction, but other than that I drive quite carefully.. hmm.. I'll check the trans fluid tommorrow, but I think you may be right!