O/D OFF light appears on dash - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

chaserthedog · 06-26-2005, 09:42

My father-in-law has a 1999 Mercury Sable LS 24V DOHC. The O/D OFF light turns on sporadically. When this happens, the speedo does not register, he experiences rough shifting, and shifting is occurring at approximately 3000-4000 rpm's. In looking at my Hayne's manual, it suggests that the VSS sensor might be the cause of this problem. Does anybody have any comments regarding this problem?

I called the parts department at the dealership to see of they had the part in stock and they told me that there are 3 vehicle speed sensors: $30, $60, & $90. Which one should I buy? I thought that he has automatic overdrive to begin with, so why would the O/D OFF light come on, even at slow speeds?

Thanks in Advance,
Chaserthedog

modenaf1 · 07-14-2005, 12:22

Quote:

Originally Posted by chaserthedog

My father-in-law has a 1999 Mercury Sable LS 24V DOHC. The O/D OFF light turns on sporadically. When this happens, the speedo does not register, he experiences rough shifting, and shifting is occurring at approximately 3000-4000 rpm's. In looking at my Hayne's manual, it suggests that the VSS sensor might be the cause of this problem. Does anybody have any comments regarding this problem?

I called the parts department at the dealership to see of they had the part in stock and they told me that there are 3 vehicle speed sensors: $30, $60, & $90. Which one should I buy? I thought that he has automatic overdrive to begin with, so why would the O/D OFF light come on, even at slow speeds?

Thanks in Advance,
Chaserthedog

How many miles on it? What you are describing sounds exactly what happened to my 96 with the Duratec shortly before the transmission turned into a bag of BB's. Sorry to break the news, but if it has over 100K, he will be needing a new transmission soon.