Checking Transmission Codes-O/D Flashing

[KCK71]

The O/D light on my "new to me" 1999 Explorer Limited has flashed occasionally when driving.No check engine light on. Nothing seems to change in the transmission, as far as shifting, such as if the tranny goes into a limp home mode with the light flashing. I tried reading the codes using a basic OBDII reader but there are no codes stored.

Do I need to read the codes right after the O/D light has been flashing (codes reset at key off)? Or are tranny codes accessed a different way? I'm thinking it may be something related to the AWD, as we've had some snow lately and it may have been trying to shift into 4WD, but that's just a guess. Otherwise it shifts fine through all gears.

 

[Dono]

The AWD will not throw a code. Its completely mechanical.

I recently had a trans issue, and read the code using a cheap ebay elm327 odb2 adapter and software (Forscan) on my laptop. This is going to be your least expensive route, unless you can find someone with the equipment to read the trans code for free.

In my case, the issue was 1-2 shift error. A broken spring in the 1-2 shift accumulator was the culprit. In the off chance that this is your issue, you can get at the 1-2 accumulator by dropping the trans pan. Its not a difficult repair.

 

[KCK71]

Thanks for the reply. Will the Forscan software pick up more codes than an OBDII code reader? I've tried reading codes with a friend's code reader and nothing showed up.

 

[Dono]

Yes, my other readers wouldn't read transmission codes either.
Forscan will read your transmission codes so you know where to start looking.