Transmission- lost overdrive?

[geosnooker2000]

Yesterday morn, I drove my daughter to school. It was cold (28 F) outside and I know that the computer tells the trans not to shift into high gears as early in order to warm up the truck faster, but after about 5 minutes, I noticed I still wasn't in overdrive at 55mph. Looked down and noticed my O/D idiot light was flashing. Thought "oh, my O/D is turned off" so I pushed the button on the end of the shifter. Then I realized.....IT WAS FLASHING. Duhhhh! Thought it might be a fuse? The hanes manual says look for a 10 amp fuse in the engine comp. maked as "V". There is no fuse maked "V". There is only 1 10amp fuse, and it is good. I have driven it 4 or 5 times sence then, and not one time has the O/D light flashed again. And yet, I still don't have overdrive. Or maybe I don't have top gear?
1996 stock Ford Explorer Eddie Bower 4x4
Transmission was rebuilt less than 4000 miles ago.
Only complaint after rebuild was that gear shifter seamed a LITTLE loose, not crisp into the "slot". But all seamed functional until yesterday.
Any ideas?
Thanks in advance!

P.S. At 55 mph, I am at about 3000rpm.

 

[rwenzing]

A flashing "O/D OFF" light is to alert you that there is a trouble code stored in the PCM. This is similar to a Check Engine Light except it is for a transmission fault code rather than an engine fault code. Have the code pulled to give you an idea where to start.

 

[BrooklynBay]

Make sure that the scanner is capable of reading manufacturer specific codes. Not every scanner will show the code which is stored.

 

[geosnooker2000]

A flashing "O/D OFF" light is to alert you that there is a trouble code stored in the PCM. This is similar to a Check Engine Light except it is for a transmission fault code rather than an engine fault code. Have the code pulled to give you an idea where to start.

That's all great and everything, but the last time I had an O/D flashing, the code was for a 2nd gear shift valve, when it turned out to be a broken band. Needless to say, my faith in codes is a little shaken.

 

[rwenzing]

That's all great and everything, but the last time I had an O/D flashing, the code was for a 2nd gear shift valve, when it turned out to be a broken band. Needless to say, my faith in codes is a little shaken.

IMO, it's much better to extract the fault code than to simply guess. The code is usually a valuable diagnostic clue.