switches 3 and 4 way troubleshooting

[al hildenbrand]

To me what is logical is to learn how 3 and 4 way switches work and ignore color schemes, you can use color to identify individual conductors for a particular install - but where people go wrong is learning black goes to "A" terminal red to "B" terminal.... and they get lost if they run into something different then what they learned, if they learn how it works it doesn't matter what color it is they just need to learn difference between a common conductor and a traveler conductor.

Amen to that!

Related to it, and not mentioned yet, is that in the really hairy DIY multi-switch / multi-light installs, the colors will change between one terminal and the next terminal (think: buried, flying or hidden, splice), for no discernible reason, so, using a continuity tester to confirm the conductor electrical path is my first choice in a situation like what the OP has described.