Hello, New to this forum. I have a 1995 F250 190,000 miles, single cab long bed powerstroke 7.3. Automatic. with DP tuner. My OD light has been coming on by itself and shifting out of Overdrive and then off again by itself back into overdrive. I can also push the button and put it back into overdrive But will still again come on by itself with no rime or reason, sometimes a lot, sometimes a little , then sometimes not at all, otherwise it seems to shift fine and the light does not blink just goes on and off. I have replaced the shift lever with a new one as I have read that is the most likely cause of the problem. This did not fix the problem. I have not been able to find a cure in any forums. Might anyone have any ideas I might try. Thanks

 

If you have a way to scan it and look for codes, I'd start there. Usually the OD light flashes when it has a code for the transmission.

 

But it's not flashing, it randomly turns on and off but does not flash, I have replaced the speed sensor that didn't help either. I've tried to scan it but I'm showing no link, also tried at the parts store they got the same message, no link, I'm assuming the tuner is causing that problem. I didn't put that tuner in, it was installed before I owned it so not sure how to get around it.

 

Old skool....
https://www.fordtruckzone.com/threads/how-to-check-codes-on-obd1-and-2-without-a-scanner.654744/