So I got this 94 V6, which now has 101,800 miles. Last December, I drove my car to the local Air Force Base, disconnected the battery, covered the car, and went on a business trip to Afghanistan for 4 months. When I came back, I reconnected the battery, the car started up fine, and I drive away. 2 days later, my air bag light comes on. I noticed also on that same drive, that my turn signals didn't work. I was stressed, and looked into it a bit. I played with all the switches and buttons, and noticed my convertible motor isn't working, neither is my rear defroster. I was relieved, since this just seems to be a blown fuse. I replaced the fuse, and everything worked. Great. Only the very next day, the fuse blew again. I figured possibly it was a faulty fuse, and replaced it. About two weeks went by, then the fuse blew again. At this point it was obvious to me that there was an electrical problem. Now being an avionics technician, trouble shooting electrical problems is an every day thing for me. I understand the basic principles of electricity, and how any electrical circuit should work. What I lack is the free time, patients with this car, and required manuals. Shops usually charge around $70 an hour just to troubleshoot it, with no guarantee on how long it will take, or what the repair will cost. Now, when you replace a fuse, and it blows again, that indicates a short, or that too much amperage is passing through that circuit. I attempted to isolate the problem. I disconnected the entire center console (if the fuse were to blow again, there is no short in the convertible switch, or wiring in that area). The fuse blew again. Next I disconnected the rear defroster. The fuse blew again. Next I disconnected the multi function switch (turn signal stalk). Guess what? The fuse blew again! Next I disconnected both the passenger and driver's airbag. The fuse blew. Next I disconnected the 2 wiring harnesses which would run up the steering column, through the part that turns (no idea what the technical term is), and up to the air bag, horn, and cruise control switches. I turned the key to ACC, and the airbag module in the dash beeped. The fuse did not blow, so I reconnected those 2 wiring harnesses that run up the steering column. In this process I ruled out the turn signal stalk, so I reconnected that as well. Now at this point, if there is a problem, the fuse will usually blow within 5 minutes of turning on the car. About a week passed by with no issue. I decided to reconnect the center console, and defroster switch, since those were ruled out. For a few more days, there was no problem. Looks like it has something to do with the air bags. Then, I reconnected the passengers side airbag, and drove to work. The fuse blew. Before driving home, I disconnected the passenger airbag. The fuse blew. (Now, when I first disconnected the air bags, the fuse kept blowing, until I disconnected the 2 wiring harnesses in steering column, which caused the Airbag Module behind the stereo to beep. After that, the fuse would NOT blow.) So, I disconnected those 2 harnesses, and turned the key to ACC. The Airbag Module did not beep, and the fuse blew. I then disconnected the airbag module. The fuse blew. Then, I disconnected the defroster switch, center console, and turn signal switch. The fuse did not blow, but I already ruled out those 3 as being the problem. I started to consider if I was at the business end of a cruel prank. If you get into someone's car, and replace, let's say, a 30 amp fuse, with a 15 amp fuse, you will have a fuse that keeps blowing out. I looked into that, and it should be a 15 amp fuse in that spot. That rules out that prank. So it appears to me, that if everything is running on this fuse, it will blow. But, if 1 or some of the components are not plugged in, there will be no issue. Now everyone's probably thinking, why would I keep blowing fuses, and not get a test light? I don't like those. I don't know where to find one, or even feel like looking. I can just keep buying fuses at walmart, since they're dirt cheap, and I'm always going there for something anyway. It also makes noise when it blow out, giving me a nice audible click when the problem occurs. I drive my car a lot these days, since time is sometimes required to blow the fuse. It will blow within 5 minutes, but when I start to disconnect and reconnect things, it could take 10 or 20 minutes. I don't have that time, so I multitask. I let that time pass as I drive the car. I also did some "jiggle tests", shake the wires hear the there, and see if that causes it. Nothing. Like I said though, I don't have the manuals to know which wire is what. Any Joe Schmoe can trace a wire's path, and look for problems. Which I did, and found none. No kinks, no burn marks, no exposed wiring. Just factory sealed wires, wrapped nicely, and untouched since the car was built. So a few weeks went by, and I was driving on a blown fuse. Not smart, considering what's currently not working. I know.
In the mean time I had a problem with my thermostat, or whatever. My car was close to overheating a few times, so I took it in to get it fixed. Same story from the mechanic. $70 an hour with no guarantee they can fix it. Turns out they don't use manuals either. So I'm better off troubleshooting this than they are, considering I work with electrical circuits every day. That's on an F-16 too, which is far more complex then a Mustang. The mechanic mentioned to me how over time it might be possible for an analog switch, or relay to require more current to operate. I never heard that, but it sounds good to me. He suggested I replace the 15 amp fuse with a 20. Now everyone knows you're supposed to use the required fuse, otherwise you can overload the circuit, and cause a fire. 5 amps though is nothing to worry about. So, I replaced the 15 amp fuse with a 20, and checked around to see what was still disconnected. Both airbags, and the airbag module are disconnected, and the plugs are clean of debris. I turned the key to ACC, and drove away. When I wanted to use the turn signal, it wasn't working. The airbag light was also on, which means the fuse blew.
So, has anyone experienced anything similar to this? I have no idea what it could be. At this point the car will be sold. The problem is, I can't sell a car with no working airbags, or turn signal. Also, no one in their right mind will buy a convertible, if they can't put the top down. Any help would be hugely appreciated, but it looks to me like this will go unsolved forever.
In the mean time I had a problem with my thermostat, or whatever. My car was close to overheating a few times, so I took it in to get it fixed. Same story from the mechanic. $70 an hour with no guarantee they can fix it. Turns out they don't use manuals either. So I'm better off troubleshooting this than they are, considering I work with electrical circuits every day. That's on an F-16 too, which is far more complex then a Mustang. The mechanic mentioned to me how over time it might be possible for an analog switch, or relay to require more current to operate. I never heard that, but it sounds good to me. He suggested I replace the 15 amp fuse with a 20. Now everyone knows you're supposed to use the required fuse, otherwise you can overload the circuit, and cause a fire. 5 amps though is nothing to worry about. So, I replaced the 15 amp fuse with a 20, and checked around to see what was still disconnected. Both airbags, and the airbag module are disconnected, and the plugs are clean of debris. I turned the key to ACC, and drove away. When I wanted to use the turn signal, it wasn't working. The airbag light was also on, which means the fuse blew.
So, has anyone experienced anything similar to this? I have no idea what it could be. At this point the car will be sold. The problem is, I can't sell a car with no working airbags, or turn signal. Also, no one in their right mind will buy a convertible, if they can't put the top down. Any help would be hugely appreciated, but it looks to me like this will go unsolved forever.
