Sorry for delay, traveling internationally at the moment. So looking at Picture 2 you will see there is a red wire hooked up to the common screw (black color). Again 3ways have load to fixture on one 3way common screw and line from breaker on the other 3way switch. I believe Romex 1 is going from Switch 1 to Switch 2 because black and white are both hooked up to this other switch and the red wire is hooked up to another wire within the switch 1 gang box.
I believe Romex 2 is your line from breaker, please verify this by using a multimeter where you remove the wire nut and put one probe on this bundle of wires and the other on the ground wires or the white wire bundle. If this indeed has 120v proceed…
Look at Switch 1 and find the black screw, that wire is your load to your fixtures - black wire from Romex 3.
So hook up the following
Switch 1 needs the master switch:
- Romex 3 black wire is your load on master switch
- Put a white pigtail wire into the neutral bundle of wires and hook up it up to the neutral terminal on the master. Also get the white wire from Romex 1 and put it into the second hole on the neutral terminal
- Disconnect the wire nut that has the red wire from Romex 1 and black wire from Romex 2
- Black wire from Romex 2 is your line
- Red wire from Romex 1 is your traveler
- put a wire nut on the black wire of Romex 1 as its no longer needed
- you can optionally turn on the breaker to verify the switch works.
Switch 2 is your aux:
- put a wire nut on the black wire as its no longer needed
- red to traveler terminal on aux switch
- white wire to neutral on the aux switch
Thats it, just like the other switch. Again just to teach you how to fish
- pay attention to the black/bronze/different color screws on the 3ways, one will have line and the other will have load
- line and load are usually 14-2 wires with just black and white, exception is fans where a 14-3 wire is often used so you can have separate switches for the light and fan.
- just because one of your 3way’s common screw is “hot” with 120v doesn’t mean the line is in that box. It is often “sent” to that switch from the other gang box just like with this situation of the Romex 1 red wire being connected to the black wire of Romex 2