If it's been raining, check for moisture in the carpet on the passenger side foot well, as mentioned if the SJB gets wet the computer will do strange things.

 

I would check Grounds 101, 102, 103 and 107 in the engine compartment. Make sure they're tight to the chassis.

 

Okay so I have 09 - radio came on by itself and then wipers - crazy electrical stuff. Took it to the dealer cause we know that it should have a life of its own. $1000 (min) to fix the junction box cause somehow I got water in the system according to Ford. Ford says no recall on Mustangs but this electrical stuff sounds on going

 

Recalls are for safety issues. This thread is also old.

 

Ford did a poor job with the seam sealing on our cars, that's where most of us get the moisture in the SJB from. There is a TSB for the water leak in the passenger side foot well, there are several ways it can get in. I took mine in after warranty so I had to pay for it, took them three tries to fix it. This is a prevalent problem and IMO Ford should've had to do a recall, and any problems caused buy it they should've had to fix for free.

 

Four year old thread. I hope the OP fixed his car by now. Lol

 

Lost the horn months ago nothing when I pushed it. I'm putting in a new radio so got most of the front apart and decided to look at the horn issue again. Read some of the threads so tried to look over the wires sort them out, tried the horn it worked. Started to put them back and the horn stopped working again. Obviously, the wire is loose somewhere not the SJB. will post again if I find where it's loose but right now the wires are spread out and the horn works.

 

Did you also read the last post submitted on this thread was from over 8 years ago

 

The car is 16 years old, they're all going to be old threads, Do you know of a newer one that helps? thanks

 

There are current threads directly related to the 2005-14 S197 models.. I suggest you start by searching the sub-forums by selecting the search function drop down menu.. When the search window box displays, type in electrical issues and you will then come across a listing of thread submissions... Choose the thread topics which are directly related towards electrical issues... Hopefully, you'll come across the latest thread submissions which address electrical issues such as yours