I have many of my exterior lights on one circuit including one room that used to be a deck but is now a room in the house. Also included are driveway lights on posts (2 posts and one above the garage) and it is these that are the culprits. All the other lights on this circuit can be turned off anf on without issue. The driveway lights can be turned on from four different places (one in the garage, one in the barn, one upstairs and one downstairs). When they are on and I turn them off, the circuit breaker trips. When they are off and I turn them on, the circuit breaker trips. The switches in the garage, upstairs and downstairs trips the breaker -- the one in the barn does not. When I turn them off from the barn, turning them on from one of the other three trips the breaker. Any ideas about this.
Thanks
Dan

Is the breaker tripping an ARC Fault circuit breaker?

It will have a test button on the front of the breaker.

A photo will help.

Nope, just a black breaker 15 amp

OK, then the CB is not the issue.

If no wiring changes had been made, in other words all has been working properly and now this problem popped up, then it is possible one of the switches is defective.

Or there is a short in the splices in one of the switch boxes.


Really weird problem.

May need to take everything apart, and start troubleshooting each cable, switch, etc.

Since this light has four switch locations, this is a 3- way/4- way switch set up.

Two of the switches will have 3 terminals (3-way), and two will have four (4-way). When taking wires off the 4 way, especially, take careful note of which wire connects to which terminal.

These switching setups are very confusing if your not familiar with it. And there are typical wiring methods, but every electrician does it a bit differently, no way is wrong, just different.

So... I take off the 3 switches that trip the breaker and then reattach one at a time to see which one trips the breaker? Now, each of the 3 (but not the 4th) trips the breaker so won't they still do it after I reattach each one in its turn? Also do I leave all the wires hanging (unattached) as I test each switch? What about just replacing the 3 switches? And why would thry trip when turning off?

Thanks for spending time thinking about this.

Taking off each switch one at a time may find the problem. Check the splices and look for any bad wiring in each box also, one box at a time.

Disconnect the wires from each switch, then try the breaker or see if you can get the breaker to trip.

This is going to be a tedious problem to find.

You really need to know how three way/ four way switches are wired.

I attached a very simple diagram, but like I said the cables can be run and spliced various ways. The switch wiring will all be the same.

The diagram I provide only shows one four way, simply imagine another in line between either 3 way and the one four way..

Hi Did you find what the problem was as I am having the same problem

Chris