I tried doing a search with no luck. I drove up to our lake house this weekend towing our boat and the truck ran great, it sat from Friday til now and for some reason all my dash lights are going on and off every few seconds, the heat is stuck on high, and the radio/gps won't turn on at all not will any of the heat or ac controls.. It starts up immediately and have good voltage. What would cause this problem?

 

Try disconnecting the negative battery cable for 5 minutes and give it a hard boot.

Denny

 

I tried that, it made the headunit turn on, but I still can't change the HVAC controls, and the guages are still going crazy. Not sure if I should drive the 70 miles home like this.

 

I would take a close look at some of the wiring to make sure some little unwanted critter didn't sample your wiring.

Denny

 

I will do that in the morning. I just took a battery from another truck and put it in, no difference. It was only a couple days and we had 5 dogs in the yard the whole time, I doubt a small critter wandered in there. According to my sct, the whole way home it stayed between 13 and 13.5 volts. But the dash was restarting every 8 seconds, and the head unit is not working again. None of the 12v outlets are working either

 

Might be the infamous connection by the emergency brake pedal

 

I will look at that, ill have to do a search first to see exactly what the problem is, I remember hearing some of you guys mention it but never really paid much attention. I did end up driving the truck home last night and it went on and off every 5-8 seconds the entire time. I also noticed when I got home that the backlighting on the hvac controls would not turn off, so I had to unplug the battery. this is my main work truck so I am out of work today trying to fix it

 

I could not figure out the problem, dropped it off at the Ford dealer last night and they were stumped, had never heard of such a problem and they sell more Ford trucks than anyone in the state, but they said they would diagnose it today. They called me this morning saying it is the ignition switch. We shall see.

 

Hey I just wanted to follow up, did you ever figure out what was wrong?

 

Just an update- they replaced the ignition switch and claimed it helped with some of the problem but not all of it. They then said the module in the radio/touch screen was bad so they ordered the part and then two days later put it in and then called me back saying that it fixed everything except they can't get volume out of the speakers so they said ford sent them a faulty module. This was a Friday so they couldn't work on it til Monday, I mentioned that I was about to leave for 10 days on a cruise so they said they will get it fixed and let me know. So they called back the next week and said that it was not the module because even with the new one they cannot get volume unless they wiggle around some plugs into the module...they said they are going to do more diagnosing and get back to me. this was at the end of last week and I'm on the cruise now and have not heard anything. I'm up over 1300 for this bill so far and it's not fixed.

 

Sounds like you have a faulty harness somewhere or a bad pcm/ecm/computer. My friends lariat had bad pins in a harness causing weird electrical problems. It took the dealer 2 tries but he ended up with new harnesses and an ecm.

 

What ever happened?

 

I should have updated this. It took them a little while to figure it out but it was the module inside the radio/nav system. It was expensive though, around 400 just for the module if I remember right