I have a 1994 dodge dokata sport an my o/d light stays on but if i hit a hole then it will go off an come back on but if i just it th4 button it dosent do anything.

 

The switch may be bad. I had a '93 I bought new and it would just shut off going down the road. They had a bad batch back in the early 90's.

 

Have you had any work done to it recently? I have no experience with the od on a dakota, but, I would start with a visual look at the wiring coming off of the transmission, and look for rubbed places etc. or loose wire touching etc. Past that, you need to take a factory service manual and start tracing the wiring. I would assume the OD goes to ground to engage, but again I am just assuming.....