Garbage disposal will not power on at all, no humming, no sound, internal status LED (if fitted) flashes once repeatedly.

Safety first: Turn off the wall switch and isolate power at the consumer unit (breaker) before touching the unit. Never put your hand into the grinding chamber.

• Check the wall outlet / spur: Verify the socket or fused spur supplying the McAlpine disposal has power by plugging in a lamp or tester. Reset any tripped breaker or replace a blown fuse (correct rating only).
• Inspect the reset/overload button: On many McAlpine-style disposers, a red or black reset button is located on the underside of the motor housing. With power off, press the button firmly until it clicks. Restore power and test the unit with a brief on/off pulse.
• Check the power cord and plug: Look for damage, overheating marks, or a loose plug. Tighten the cord clamp at the base of the disposal and ensure the plug fits firmly in the socket.
• Inspect internal wiring (advanced): With power isolated, remove the lower access cover to inspect the terminal block where the supply connects to the disposal. Tighten any loose screws and check for burnt wires. If wiring is damaged, replace the cord set or have a qualified electrician repair it.

If the unit still will not power on after a reset and wiring check, the internal thermal protector or motor windings may be open and the motor assembly will likely need replacement.