I got a 03 f150 with the 4.6 and I installed a sony radio in it. Well now I've no cruise control and ran the self test and it blinked 3 times. Meaning defective circuit or deacticator switch how do I know what it is?

 

Well, start by checking the deactivator switch circuit. The speed control can't operate if that circuit isn't supplying power.

 

I looked at the circuit everything seems to check out

 

Since everything checked out, then it should be working.

 

It worked fine until I put the new stereo in it and I know it gets power from the radio. I'm basically wondering if anyone knows how its wired

 

When you put the new stereo in, how did you wire it? Did you use a wire harness that was made for your truck to connect to your new stereo? Or did you splice any wire at all in this process?

Mitch

 

The speed control does NOT get its power from the radio. Where did that idea come from?

Look, either you have a coincidental failure (it just happened at the same time) or else you've managed to alter or miswire something. Usually, it's best to reverse whatever you did, take it back to original configuration, and then start troubleshooting if the fault is still there.

 

I used a wiring harness for my truck it was just a plug in and go type of thing.

 

My Dads friend is a ford engineer and said that the cruise control was wired through the radio so o just assumed he was right.

 

Humm.. No idea, if you used a wire harness, then that eliminates a lot right there... I did the same thing on my 97 F150 and no issue with the CC..

Fuse maybe?

Good luck!

Mitch

 

Thanks, I also read in another forum that the white and green wire (auto volume) doesnt have a wire in the harness so If i conmect it i should've power for CC