I have a 1994 Ford Taurus SHO and ever couple of weeks this OVERDRIVE OFF lite flashes for a couple of days then goes off. I suspect it has something to do with the transmission and its electronic sensors. Take your car to a transmission shop and hook up an analyzer to the ECM for the transmission. It also can be related to the Vehicle Speed Sensor. This sensor feeds to the ECM and if defective will disable the electronic Overdrive.
It shows that there is a problem with the transmission. Just like the check engine light, the overdrive light has codes that tell you what is wrong with the transmission and the various components connected with it.
Take it in. There is either a problem with your transmission or with the overdrive switch itself. Overdrive switch should be a lot cheaper to fix. I'm assuming the light not only goes on, but the overdrive physically turns off as well when the light is on.
Is door ajar light on also?
Usually a flashing Overdrive light on any Ford with an Automatic Overdrive is a sign of an internal failure. Seek the assistance of a qualified mechanic or transmission repair shop.
something is wrong in the transmission. It will have to be diagnosed. You probably have a bad shift solenoid in the tranny.
It's telling you there maybe something wrong with your transmission. Have the codes read and go from there.
Flashing overdrive light, or one that goes out and won't come back on means you need to have your transmission checked. I believe in a 99 they have a computer hook up they can use to see if they can figure out what is wrong with the transmission.
somthing is wrong with your car.
My knee-jerk answer would be a TCM (Transmission Control Module) problem, but have a shop hook up a scan tool and they can tell you what is wrong.
No, something is wrong.
I believe it is Jason Miller but I could be wrong