Okay. We need to narrow this down. First, the fuse that is blowing is the one in pic 1. If you note, the fuse powers the front signals as well. Do the front clearance lights. Do they work when the fuse is blown? They shouldn't, but you mentioned all others work. Please confirm that for me. Also, confirm if the license plate lights are working. They, too, shouldn't be working.
Next, if you look at pic 2, you will see where the wiring color changes. There is a connector that joints the two different wires and then there are several splices in the power supply.
Any one of them could have caused a short if they came apart, but at this point that is doubtful. However, there is one thing that can be causing the issue. Does this vehicle have a factory trailer wiring connector? If you look in pic 2, you will see I circled the splices. Additionally, I circled the trailer wiring harness. If the vehicle has one, see if there is a connector you can take apart to the plug and then see if the fuse blows. It isn't uncommon for shorts to happen there.
Let me know what you find.
Joe
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Friday, February 14th, 2020 AT 8:16 PM