Help me figure this out...

[hankgood]

My elderly father-in-law asked me to look into a problem he was having with some exterior lights at his two-story home.

Once I dug into it I found that someone had installed a X-10 switch and two Leviton 6375 Fixture Relays wired to two outdoor fixtures. The single remote switch is rarely used and recently had the following trouble with no known cause.

One light will not come on and the other will not go off - the switch has no effect.

Where should I start ? - I'm thinking maybe replacing the switch.

Yes - one more thing - Comcast recently installed a ethernet device that transmits broadband internet over the house wiring. It was about a month before this problem arose.

Thanks,

Ha

[gil shultz]

Good Evening,

Assuming the X10 is ok and when the etherent was turned on the X-10 quit working the ethernet is swamping the front end of the receiver(s).  Power down the ethernet and if the problem goes away you found it.  If not you will be having some fun. 
Gil Shultz