1999 Windstar Blinking Overdrive Transmission Light

This is a warning from the transmission that it detected a problem. The transmission often has a separate computer, so it may not show up in a regular code scan.

The trans has two sensors one is called the tps trans position sensor for your shifter they can go bad. Alos the VSS vehicle speed sensor can go bad that will kick the light on and the engine light on as well obdII code will be 0500 vss sensor. Hope this helps you.

well OFTEN does not apply to this vehicle so bringing that up is a complete wastse of time! P.C.M. controls trans functions,but thanks for the useless advice.

Scan for codes,diagnose based on codes or symptom,then do repairs,then recheck for other problems.Whats that? youdon't know how to do all that? thats why they invented mechanics,plumbers,masons,doctors,electricians,mailmen,etc....spend the money!