I never turn the cruise control switch on. Today I was driving home and decided to turn it on and it doesn't. Does anybody know what might be the problem.

 

The same thing was happening to me,except it was when I started it up in the morning. I was able to eventually get the cruise to work, but often had to wait until I had driven a number of miles. Turns out it was a cruise control limiter switch on the clutch. It had gone bad, so wasn't working correctly. I took it in to the dealership and it was completely covered by warranty.

 

I have an automatic though

 

if your talking about the light it will not come on until you hit the SET button. Hit on then set and you will see the green light.

 

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http://2005stang.com/images/stangdocs/manual.pdf
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