Coming back from a trip last weekend I tapped the break to kill the cruise control and when I went to resume it would not work. I tried turning it off and on several times but no go. It had been working just fine for the previous 1500 miles of the trip. My guess is a blown fuse but I am not seeing which fuse to check (at least nothing clearly identified as cruise) in the owners manual and I sure don't want to start pulling them one by one to check.

Can anyone point me in the right direction? Thanks.

 

My brake switch went bad and caused my cruise control to go out. It's right up under the dash above the gas pedal on the right. There won't be a code, or a light, but when I had it in for service and told them about it they said they have replaced quite a few. Might be worth looking into. I believe it was the stop lamp switch that they replaced. Can't find my ticket just yet.

 

i had a car once that the brake switch was bad but if i lifted the brake pedal with my foot i could get the cruise to work.

 

When you say the switch went bad, I assume the brake lights quit as well? The brake lights are working fine when I step on the brakes.

Does anyone have a wiring diagram that specifies which fuse to look at?

 

No, the brake lights worked fine. That's what was so weird. It would happen intermittently at first, then it just stopped altogether. When I took it in, I told them the cruise control had stopped working and they just knew of the switch. If you look under the dash, up under the ash tray area, is a white switch which is the switch they replaced. It has to do with the sending of a signal to the cruise control unit that the switch has been closed. It still operates the brake lights, it just tells the cruise control that the signal is being sent all the time, therefore disabling the cruise control. But you keep looking for that fuse. It doesn't exist. The cruise control is hardwired to the PCM through the clock spring.

 

I would try replacing the deactivator switch. FWD switch on underside of master cylinder. Usually an easy fix. Here's one:

 

Thanks, that is the info I was looking for although it seems odd that there is something electrical with no fusing. Now if the wind will quit howling and it will warm a bit I will get out there and check it.

 

Thought I would update this thread. The cruise works fine again. Don't ask me why as I haven't a clue. My son's 7.3 was being cantankerous starting on a particularly cold day and we used my truck to jump his. After that the cruise was working again.

Now the back up alarm is working when it wants to, well, more specifically it will sometimes screech when there is nothing at all behind me. Oh, well, I can live with that as I sometimes think I am too reliant on it anyhow.

I am convinced the truck has gremlins though.

 

Typical behavior of a deactivator switch going bad. They sometimes fail intermittent. Good luck.

 

Just looked at my paperwork from when mine was fixed. The brake deactivator switch was what they replaced. Good place to start.If it does like mine, then it will stop on you sometime in the future again. Typically mine would start working, then stop working, till finally it just stopped working most all the time. My paperwork says they found a code, so maybe if you know someone with a code reader it will tell you something.

 

This is the part I was looking for. Thanks Rudiak.

 

I have a Scanguage on the truck and I had not thought to check for a code since there was no CEL. I will check it now though. Thanks the for the tip.

Just as a slight diversion, any AutoZone, at least the ones around here, will check codes for you. They will not clear them though.

 

Anyone have a part #?

 

The part # is 3L3Z-9F924-AB. The link for the part on Ford's site is Buy 2008 Ford F-250 Super Duty Parts | FordParts.com

 

Thank you!!!