Hi, I am a professional certified mechanic, with an engineering background, and 35+ years experience. I will do my best to assist you. Also keep in mind I don't know if you are a pro or a novice, so feel free to add any additional info at any time.
I specialize in electrical problems and I will try to point you in the right direction on this. If the fuse blows as soon as you turn the key on, it makes it a lot easier to find the problem. I know it isn’t good that a fuse is blowing, but an intermittent fuse blow is a really tough to solve. Since you didn’t see a short inside the transmission, we will have to explore a bit to find the problem. I would unplug the transmission electrical connector and put a new fuse in it and see if the fuse blows with the ignition on. If the fuse doesn’t blow then you know the problem is inside the transmission. That will take a little exploring inside the transmission.
If the transmission isn’t the problem then you are going to get into the electrical system to find the short. BotXXXXX XXXXXne is when you have this type of issue no one can tell you what the exact problem is. You already had a dose of that when you opened up the transmission looking for the short. This is a lesson I have learned over and over. There is an inexpensive tool that will allow you track this type of problem. I have used these many times, and cant over stress how well they work. You can find nearly impossible to locate shorts with these tools. I will post a link HERE where you can get one. Without this tool you might have dig a lot deeper to find the problem. The PCM (power train control module) might have a short in it so be on the lookout for this. Go over all of this and if you have any more questions at all, I am here to help. Good luck with it, have a great day, and Thanks for using Just Answer.
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