Dome light circuit problem (1 Viewer)

[CharlieS]

Except the rare things that involve alternating waveforms (like O2 sensors). Those require a little more knowledge.

 

[jonheld]

where would you have a guy like me start to learn how to read those electrical wiring diagrams, then put them to use in tracking down issues?

In addition to what @Malleus posted, I would suggest a book or an online tutorial for basic DC circuits. That's going to cover more than 90% of the 80 Series. Notable exception would be the ECU, but even that can be diagnosed to an extent with a decent meter.
Learning the basics of DC circuitry, purchasing a good meter, learning how to use it, and learning how to read schematics, will put you on the right path.

Just keep in mind that I've been doing this kind of thing for over 40 years. I'm old and crusty with a bit of mold around the edges.
Don't get frustrated, take your time, and practice over and over again.

 

[man0fsteel]

There are Toyota technical training publications, if you want to know how Toyota goes about it. I'd start with the Electrical Wiring Diagram(s) for your truck(s). The first several pages explain basic troubleshooting. There are also Toyota publications on how to use a digital multimeter (DMM) for troubleshooting Toyota systems.

Look in the Resources section under the heading "UNCLASSIFIED":
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This is a great starting point. Thanks - So cool that Toyota has publications on how to use the DMM among other things!

 

[man0fsteel]

Except the rare things that involve alternating waveforms (like O2 sensors). Those require a little more knowledge.

Yeah for sure. But for now, it's baby steps for me.