In the first 3 way switch box connect the pair of wires leading to the 4 way box to the out pair of screws on the switch. For example if you have a living room that has three openings you need a four way switch in order to control the lighting in the room.
![Flashers And Hazards](http://www.netlink.net/mp/volks/schem/bus_4way.gif)
Flashers And Hazards
4 way switch in and out. The mechanics of this switch are simple in that they either switch the travellers straight through or criss cross them. Connect the remaining wire to the in screw. A 4 way switch has 4 terminals or poles. Actual toggle position can vary with make and model. A 4 way switch has four terminals do not confuse with and purchase a 2 pole switch by mistake. Remove all of the switches so you can access the switch terminals.
The wire connections do not have to be removed. A 4 way switch must be wired between two 3 way switches as shown in the diagrams on this page. A 4 way switch has five terminals. Each pair of traveler terminals should be wired to the traveler wires from one of the 3 way switches in the circuit. When the switch is operated current will either travel straight through or crisscross. The circuit should now work.
4 way switch not to be confused with a 2 pole switch. Each opening from which you can enter or leave a room should have a switch that controls the lighting within that room. Test a 4 way switchturn off power to the switches at the circuit breaker and using a tester make sure power is off. One ground and 4 circuit terminals divided into two matching pairs called travelers. Two terminalpoles are labeled in and two are labeled out pairs of wires called travelers will connect to each side. Repeat for the other 3 way switch box.
Using a continuity tester check continuity between terminals as shown. Four way switches can come in handy in large rooms that have many door openings or exits. The 4 way terminals are labeled in and out two of each.