Trying to install GE 3-way with 12722 and the add on 12723 but missing the neutral where the addon goes

[jhamstead]

I have made some diagrams for someone else but you can refer to them. Look at the bottom two and only the left two switches. That is how they should be wired.

Change 3 way switch to 4 way with smart dimmers

Here are the 4 possible combinations of wiring you may have (if power from breaker is coming from your light then this is not possible). The two switches on the left would be your existing 3 way switches while the one on the right is the single switch. The first light is the one controlled by the 3 way, the second the one controlled by the single switch. These diagrams show the new 3-wire line you would need to add. [image] [image] [image] [image]

Modified ones attached below