Hey guys, I have a 2004 F-150 Supercrew 4x4 5.4 anyway my cruise control works great when it's cold outside but as the day warm up the cruise progressivly gets worse, ie starts to cut out and then just quits working alltogether. It does not work at all in the summer. I had the dealer check it before I knew that it would work when it was cold out and they said it was the transmission interlock switch.

Has anyone else had this problem?

 

Yes, when your cruise stops working try to shift out of PARK without pressing on the brake. If you can shift then your interlock switch is failing. Seen it on a few. It is on the console shift trucks though, haven't had any colulmn shifters do it yet. Also seen a few buttons on the steering wheel fail as well as a clock spring. Come to think of it also had a few radio's go bad that took out the cruise(the radio is on the same circuit to the pcm as the cruise and leaks voltage to the pcm when bad). Good luck!!

P.S....If you disconnect your radio when the cruise stops working, and it starts working again, the radio is your culprit!

 

The interlock switch is out, but I'll try the radio and see if that's it. Thanks