Before You Start

Safety first — turn off the circuit breakerGo to your switchboard and turn off the breaker for the circuit you are working on. Use a non-contact voltage tester to verify there is no power at the switch before touching any wires. In Australia, electrical work regulations vary by state — like-for-like switch replacement is generally considered DIY-permissible, but if in doubt, use a licensed electrician.

Step-by-Step Switch Replacement

  1. 1

    Turn off power and verify with tester

    Switch off the circuit breaker for the room. Toggle the existing light switch on and off to confirm the light is off. Use a non-contact voltage tester at the switch to confirm no power.

  2. 2

    Remove the cover plate and old switch

    Unscrew the cover plate. The switch is held by 2 screws into the wall box. Remove these and carefully pull the switch forward — the wires are still connected.

  3. 3

    Photograph the wiring

    Take a clear photo of which wire connects to which terminal before disconnecting anything. This is your reference for reconnecting. In Australia, active (live) wire is typically red or brown, neutral is black or blue, earth is green/yellow.

  4. 4

    Disconnect old switch and connect new one

    Loosen the terminal screws or release the push-in connectors and remove the wires from the old switch. Connect to the new switch in the same configuration — same wire to same terminal position. Tighten terminals firmly. Ensure no bare wire is exposed outside the terminal.

  5. 5

    Fold wires back, screw in and test

    Gently fold the wires back into the wall box. Screw the new switch to the box. Attach the cover plate. Restore power at the breaker. Toggle the switch — the light should turn on and off correctly.

Replacing with a smart switchSmart switches (Philips Hue, Kasa, Ikea) require a neutral wire in addition to the active and earth wires. Many older Australian homes have two-wire systems without a neutral in the switch box — check before purchasing a smart switch. If there is no neutral, choose a smart switch designed to work without one (like some Lutron models).

Frequently Asked Questions

A one-way (single-pole) switch controls a light from one location only. A two-way switch controls the same light from two locations — common for hallways and stairs where you want to turn a light on at one end and off at the other. Two-way switches have three terminals instead of two. If replacing a two-way switch, you must replace with another two-way switch and maintain the same wiring configuration.
Most likely causes: a wire came loose during reinstallation (pull gently on each wire to check connections), the wires are connected to the wrong terminals (recheck against your photo), or the circuit breaker tripped from a short (check the breaker). Turn power off before inspecting. If all connections look correct and the breaker is on, the new switch may be faulty — test with a multimeter or try a different switch.