Mattax said

Post some close ups of this cleaner air retrofit and maybe we can figure out what it does and how it was wired in.

For figuring out the electrical issues, you will need a multimeter and a clipboard or notepad.
I guess what you're thinking about a video call is that you could immediately show what the person was asking about. I can't help with that, but if you post photos we can walk you through this. The design of the main power and charging system is pretty simple. The routing has several junctions made with connectors where measurements can be made. Most of it can be done from the engine compartment side of the firewall.

The basic scheme is this.
Power is supplied from either the battery, or the alternator. The output from both is connected to the power feeds for the various circuits by a welded splice. When a circuit is closed, current flows from either power source to the welded splice then to the item(s) that will complete the circuit back to battery negative or alternator ground.
View attachment 1715566574

When the key is in RUN position power should be available in the wires labeled J2
View attachment 1715566577

When the voltage in the J2A wire at the regulator is less than 14 Volts, the regulator lets current flow through to the alternator's rotor. Current flowing through the wire windings in the rotor create an electromagnetic field. That's why those connections are labled field. The end result is power generated available to the output wire, labled R6.

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