ajschwab2004

I got 2005 F150 5.4 and today when I was driving on the highway I was using the speed control and out of nowhere it shut off by itself like when you press the brake and it deactivates, but I never touched the brake pedal. It did this 2 times while I was driving; never had it a issue with it before. Just started today!

BadFish523

1st and simplest check your 3rd brake light bulb above the cab. It could be partially burnt through and making good connection some of the time. That bulb completes the circuit for the CC. Do you have LED bulbs in any of your brake lights?

ajschwab2004

I still have the original stock brake bulbs. The CC works but today I had it on for 10 mins then it shut off by itself; tried again had it going for 2 mins and shut itself again, but when I get off work I will see if all the brake light bulbs are working.

BadFish523

Take out your 3rd brake light and look at it. Make sure is not partially burnt and makes connecting part of the time.

MikeBrusoe

check the brake light switch on the brake peddle mine went bad and I had no brake lights and no Cruse Control.....

elricfate

Yea. Third brake light or regular brake lights. Brake light actuator on the pedal. Assuming you've had this since day one, you would know that all the bulbs were regular bulbs. Assuming you bought this from someone, if any of them are LED, it could cause the same issue if they didn't replace the relay. Our CC relies on voltage to detect if the brake pedal has been pressed, if there's any kind of short, it's going to glitch it off.

ajschwab2004

Well I haven't checked my brake light bulbs or the third light brake bulb, but I tried it last night going home after work and it worked fine all the way home and again this morning on my into work it worked fine so definitely something weird happening.

BadFish523

Like I said sometimes a bulb will burn through then when bouncing around will touch back together and the current will slightly fuse the element back together. If that is the case it will happen again. Glad it's working now though.

atlbraves

I have an 06 f150 the other day went to set cruise control truck shut off I was able to start back up but everytime I put on cruise the truck died . found this forum and I had changed my third light brake bulbs to led went and changed them back to the regular bulbs truck works great now thanks for the info

BadFish523

Glad we could help! Although I'm not sure why it would kill the truck when this happens? Stick around and share your experiences and your truck with us!