These are the OEM Ford wiring diagrams, it looks like the aftermarket ones may be incorrect which is common on older service info. Hopefully there isn'tt too much going on in diagram 1 below, but it's actually very basic, each rear 02 will have 2 wires the same color at the sensor and those will be the heater circuit, but I would do all wire repairs before turning the key on, so no fuses pop. You can check the wiring at each 02 connector for any shorts to ground or continuity to the PCM connector using a multimeter set to read resistance (Ohms), you may know this stuff already, if so just let me know and I won't post so much information.
If the wiring is really bad, you may want to run new wire as far forward as you can, until you reach some wiring that has insulation left on it to identify wire colors. At least that way you'll know which wire should go to the correct 02 connector.
The transmission diagram shows where the 02's harness runs to, along with the vehicle speed sensor. I'm not sure how much around the transmission was damaged but just let us know what you need next. I see the fuel pump power comes from the fuel pump relay to the fuel shut off switch (Inertia switch), it branches off to the PCM from that point as well, so if the fuel pump relay does not activate, the PCM will see power missing on that circuit and can set a code for the fuel pump relay. I will post that next.
https://www.2carpros.com/articles/how-to-use-a-voltmeter
https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester
https://www.2carpros.com/articles/how-to-check-a-car-fuse
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Monday, July 28th, 2025 AT 9:02 AM