I'm working on a 2007 Ford Mustang. The O/D light is flashing and the transmission has some rough shift transitions.
When I use OBDII to read the codes, there are no faults found, no faults in storage.
Huh? Never seen this before. I would have thought that something that triggers a blinking OverDrive (O/D) lamp would set a code somewhere. Now my OBD2 scanner is sorta old. I think I bought it around 2008 or so. But it has always performed well.
Or is there a separate special systems tester of some sort to read transmission fault codes?
I'd like to understand why the lamp is blinking.
Note: the transmission has 120K miles, and I doubt the fluid had ever been changed. I pulled the drain pan, cleaned things up, no metal bits in drain pain. Replaced filter and what oil I can. Still shifts rough.
Anybody know how to read the code behind the blinking O/D light ?