Suzuki Repair: Suzuki sidekick O/D switch, colorado rocky mountains, suzuki sidekick

Question
I have a 93 suzuki sidekick and my "O/D off" light turns on and off rapidly and intermittently after reaching about 45 mph, causing my car to sputter & stall.  I have disconnected the O/D wire plug to see if it stops, but it is still misfunctioning.  do you have any idea?

Answer
In reality, it's not O/D, but just fourth gear.  It sounds impressive though.  You most likely have a broken or rubbed through wire between the switch and the trans control module.  I've never had and never seen this model in the area where I live (The Colorado Rocky Mountains).
I'm sure a decent wiring diagram could make diagnosis easier.