2010 Expo Horn / cruise not working

[PTR-Jason]

Hey all,
I hope this is the right place to post.

I am issued a 2010 XLT as my take home patrol vehicle (deputy sheriff).

Issue I am having is after it sat for about three months, the battery was shot. It was jumped and pretty much ran on the alternator as we had to use it to go up to the mountains for a case. On the way there we noticed cruise control was not working. Figured it was just a fuse. We met up with another deputy, and while talking to him, we pressed the cruise control switch for the hell of it. Horn just blowed constantly, never turning off until we had to hastily pull the battery. When we reconnected it, the horn went off again, when headlights were on, horn stopped, turn them off, horn goes on. We ended up pulling the fuse for the horn.

So not that the battery is replaced, horn still blows constantly.
Cruise control does not work.

I checked all of the fuses that I can find in the fuse boxes, and can not find anything that stands out. This is a major problem as like most police vehicles, the horn is tied into the siren.
Things I have noticed are this:
-Dash light dimmer switch will buzz when it is at different levels
-siren and dash lights work fine when at a setting that does not buzz, but if I accidentally hit the horn pad or the cruise control switch, half of the cruise switch will black out and my siren will come on when the control box is on as if the horn is activated, (how it is supposed to work) but it constantly on not momentary. (I don't expect most of you to know how the siren portion work)
-the cruise control and 4x4 switches stay lit constantly all the time, even when off and parked
-when the cruise control switch half blacks out, turning off the vehicle and turning it back on resets it until it is pressed again.
-when the cruise control switch is pressed, the lights for the switch, AND the 4x4 switches black out while the switch is pressed.

I replaced the headlight switch, didn't help
I also took the horn pad/air bag off, the springs for the horn worked how the seemed they should. No broken or missing plastic. Nothing looked like it was getting grounded.
I disconnected the cruise control switch, didn't help.

I think I covered everything I have noticed and that I have found or tried.

Is there anything else that I can try?

Thank you for any help. I am at a complete loss. We usually do all our work in house as the closest dealership is about 2 hours away.

 

[Flag Gibby]

Check the voltage from the alternator under load. I suspect that it might have to do with the alternator since you replaced the battery. However, the vehicle needing a jump after setting for 3 months bothers me because it should have had enough of a charge still in it to get it started.
The other thing is to look for wires under the dash or hood that are exposed that could be causing a short.

 

[PTR-Jason]

I'll have to get a volt meter. I have no clue where I put mine. And the truck was sitting for three months in very cold weather and snow. Something was draining the battery. But I wasn't there to park it, so I do not know. I think it may have been the 4x4 lights behind the switches, I can not remember if they stayed lit before I went to the academy or not.

But my personal vehicle sat for four months in the same cold weather, and it started right up, and I mean right up with no cranking or anything.

 

[PTR-Jason]

I am not sure I added, but we pulled the fuse for the horn the day it started sounding, and it is still out so there is not horn fuse under the dash.

But something is still grounding it when it is pressed or the cruise control button is pressed because the siren will act as if the horn is pressed. Until the car is trend off and turned back on.

 

[Flag Gibby]

Exactly, that is why I am suggesting checking the alternator and looking for wires with breaks in the shielding because in my mind something is slowly draining the battery faster than normal with the ignition off.

 

[PTR-Jason]

Sooo more info to add today. I think I narrowed it down to a short in the wiring harness along the steering area. The day before yesterday I noticed it was turning the siren on when I made a hard left to turn around on someone. It wasn't doing that before.

So today when I was on patrol it started doing it again. I pulled off and got to an area down off the highway and decided to pull the panels off under the steering wheel under the dash. I played around with the harnesses, didn't see any cuts or worn areas though. I was noticing that I could hear the relay clicking when the wheel was turned all the way to the left. Well I just wiggled around the wires and then I noticed that the relay was no longer being locked open when the cruise buttons were pressed or with the horn. And the headlights could be off or on, and the siren would not go on with the horn.

I didn't want to test how long it would stay working, so I did not put the fuse for the horn back in. Knowing my luck I would get to town and it would just start blasting again.

However driving down the highway when it got darker I noticed that the back lights for the 4x4 and the cruise and audio switches didn't work now. Oh well no biggy. So I tested the cruise control by chance and it worked!!!!! And it didn't turn on the siren when all the emergency lights were on. SCORE!!!!

Well I went to dinner, turned off the car and when I left and got the highway I looked at the steering wheel and noticed the lights were back on now. Fearing the ghost in the machine had returned I hit the cruise, still worked. Sweet. Next fearing as soon as I turned on my emergeny lights the siren would come on, tested that and nothing. Very sweet!!

I did notice that the back lights stopped working as soon as I cranked the wheel all the way to the left, but everything else still worked as it should.

So I am pretty sure it is just a short in a wire getting a ground where it shouldn't and causing a heck of a lot of problems.

On my next day off I'll take it apart again and try to find a short somewhere.

Next thing I need to tackle is the Auto 4x4. I pulled the fuse for that too since it has has always engaged and disengaged at random times. Usually slow speeds like 15-35 mph. And even at highway speeds. It kept making pound clanking noises. It had been that way ever since I got the vehicle in June. It only has 74k on it. I just have to put the 4x4 fuse in if I plan to go off road at all. 4x4 works fine when it is selected it, but the auto 4x4 is causing all the clanking and jerking. Even when it's not doing it, you hit a rut in the road and it engages on a tire in the front and wants to pull you that way. I always thught it was the steering. But after pulling the fuse for it, it drives and steers perfect now. A lot more comfortable and safer to drive.

 

[Flag Gibby]

Wow, talk about a bag of worms... no way that I would be able to put up with that for very long especially if I had to deal with it the whole time while on patrol.
I would start by checking all of the wiring harness connections on the steering column and on the brake pedal assembly and as far as the 4x4 goes check the harness that feeds the transmission/transfer case. Good luck.

 

[theruffryder]

Any updates? I have a similar problem with our 06 Expo Eddie Bauer. Nothing seems to be working on the steering wheel.

 

[PTR-Jason]

Sorry I havnt been able to do anything to the unit. But so far everything is remaining the same. Still have the fuse pulled for the 4x4 and the horn. But no other issues as of yet. Maybe tomorrow I will try to find the problem in the harness under the steering wheel.

 

[PTR-Jason]

So a little more info. Past few days the cruise no longer works. So yesterday I took off the covers under the steering wheel and on the wheel itself and looked harder for a splice or anything like that.

I found nothing. I even put the fuse for the horn back in and horn was not working either. The only thing that works for the switches is the audio controls on the right side of the wheel.

I am thinking that there is something loose in the area where the wheel rotates, as the wires and plugs under the horn cover and on the steering column are fine and plugs appear fine. But I can not see the three inch area where the wheel turns and the plugs plug into.

So for now I am done messing with it, until I can get permission to take it to a ford place, even if I have to pay out of pocket.