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1) Temporarily back out each of the 3-way switches from the wall box but do not disconnect any wires. I need to know the wire color that is terminated to each 3-way switch on it's black screw. It will also be labeled as COM (common). Right/left and/or top/bottom screw colors don't' mean anything, I only need to know the wire color that terminates to each 3-way switch black screw?
2) Your previous comments as shown below are confusing. Which is it? How can the breaker trip yet the light works?
"I've attached the new fixture, but when I turn off the light switch (it's a 3 way) at either switch, the breaker trips"
"The new fixture is currently on right now and is lit up".
3) How was the original light fixture spliced to the ceiling box? Which wire colors were used? The original light fixture black wire was either spliced to a black or red house wire plus spliced to the house white neutral wire?
4) How many light fixtures are controlled by the 3-way switches?
5) Do you have either a 2 wire lead AC voltage tester or an AC voltmeter available?