Overheating issue, was the wire laying on something that got hot? I was more concerned with something having shorted out and causing too much current flow on that wire, such as if a 12volt feed shorted to that ground wire and burned it up. Technically that must have caused a blown fuse, but some direct power feeds coming off the battery positive are not fused until they get to the fuse panel then the power runs out to components. Since the Mass air flow (MAF) sensor ground looks intact, you could check the resistance from that black/white wire to battery negative and see what you. There should be very low resistance. Although this is not the correct way to test a wire, it will tell you if the wire is an open circuit somewhere. Because there are so many components using this ground, it would be good to check the wire from each component to battery negative. Where exactly is this wire damaged? Right at the ECM? It looks like it's missing a lot of insulation in a couple of those pictures.
These 2 pictures are very concerning, what is this connector in the 1st picture? That is going to be difficult to repair being that the insulation is missing all the way up to the connector pin. And the 2nd picture, why is the wire bare inside the conduit? I can try to locate the connector in the 1st picture, and I assume the 2nd pic is close to the battery because I see a large red cable next to it. If the 1st pic is a connector in series which is just a section of harness that disconnects, you could bypass the connector at least for the Black/White Ground wire. Or you will have to de-pin that wire and try to repair it, which will take a lot of time. So on the other side of that connector, you should have the same wire with its insulation on it, and you could cut the other side, put a crimp weather seal butt connector on it and run a wire around the bulk connector bypassing it. Unless that's the ECM connector I'm looking at.
As for the 2nd pic, It's tough to tell what I'm looking at there. Is this down on top of the transmission? And is the black conduit melted too?
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Sunday, September 10th, 2023 AT 9:25 AM