Electrical Question #15 Need Help Please, I'm totally stumped this time Options

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I'm going to have several electrical questions. 1st, Is pin #8, on the 14 pin plug at the relay board, the only switched 12v+ source in the engine compartment? TIA, Kent

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Post #13. I'm at a Baker's Dozen so I'd better start off with thanking everyone of you guys for all of your help. I've learned a lot with your help but once again I'm stumped and need to run this by you genuis'.
When I turned the ignition switch to "on" yesterday I heard a faint squealing noise from the frunk that continued after starting. My first thought was the fuel pump but after flipping the "fan override switch" the noise stopped as the fans came on. This time my first, or should I say second, thought was that one of the fans had been in a bind after adding the duct work and now cleared. Yea right. So later in the afternoon when charging the AC I flipped the fan override and nothing! (IMG:style_emoticons/default/WTF.gif) Checked the fuse and it was fried. No, I mean fried as in melted and sticking to the plastic fuse holder. Needle nose pliers and a pocket knife later I am treated to this:



Oddly enough it is on one terminal only and that terminal is the Battery side. As you see in the next pic the wire melted/distorted the insulation a few inches back but the other side is OK. Might be worth mentioning that the plastic holder became hot enough that the spade terminals float in that case and can touch one another bypassing the fuse. Might not matter in this case. (IMG:style_emoticons/default/confused24.gif)



I remember chasing a short last summer that turned out to be this New distribution box. POS. I only mention this because it was a loose connection that eventually separated because of the melting/bubbling of the plastic. This happened because I did not check the tightness of the screws on the back before installing. (IMG:style_emoticons/default/headbang.gif) Anyway, the milky area was the problem area and guess what? That was on the battery side also!



Am I seeing a pattern here? Did I have a bad factory crimp at the spade which caused resistance eventually melting that insulation and shorting out? I'm pulling 9.7A with both fans on, 10ga dedicated circuit, 20A fuse per Derale controller. Another tidbit: the fan controller uses negative switching. I just supplied 12v & ground to it. Relay, fuse and control board are all factory. One last piece of info. The fan controller is mounted on the driver wheel well about 8" from the gas tank. Until I ducted the radiators last week the gas tank would become very hot from the radiator exhaust resulting in vapor lock. Could that have damaged the board? This I ask because of the squealing noise I mentioned earlier. Why did the controller or it's relay squeal? The fan override switch was not on and it was a cold start so it should not have called for them to come on either. I failed to mention that when I first discovered the melt down I replaced the fuse, taped the bare spots and all was normal. However, when I turned the switch to on that evening the squeal returned. I'm replacing that fuse link but it won't be here for a few days so I thought I would run this up the pole for opinions in the meantime. TIA, Kent