The short answer for MM models
An Avanti MM microwave that trips the circuit as soon as it starts is telling you about a short under load, most often in the high-voltage section. Nothing about that is owner-diagnosable, and repeatedly resetting the breaker to see what happens is the one thing not to do.
What the owner sees
- The plug or the socket is hot to the touch — A connection fault outside the oven, and it is a fire risk in its own right.
- A hot or acrid smell during or after use — Overheating insulation or a component, and a reason to stop immediately.
- The oven runs but the house RCD trips intermittently — A leakage fault, which needs a technician with the right instrument.
- Lights dimming elsewhere in the house when it starts — A heavy load on a circuit that is marginal for it.
- NEAR MISS — the oven simply will not start — That is a start fault and it has its own page and its own list.
Likely causes on MM, ordered
- High-voltage component shorted — Ranked first for a breaker that trips under load, because that is the only section of the oven that draws heavily enough to do it.
- Control board failure — Last on the list, and it rarely presents as a tripped breaker.
- Waveguide cover burnt through — Food residue on the cover chars, then arcs, and it is a known and preventable cause.
- Earth fault in the appliance — A tingle from the cabinet or an RCD tripping, and the oven should be unplugged and left.
Working through it in order
- Where to begin — The order below follows the ranking rather than the machine: zero of the four causes above cost nothing to rule out on MM models, so they come first.
- Look at the flex where it enters the cabinet — Wear at the strain relief is common on any appliance that gets moved and it is dangerous.
- Ask what else is on the same circuit — A standard household branch circuit is fifteen or twenty amps at one hundred and twenty volts, and several appliances can exceed that.
- Note whether the breaker trips at plug-in or at start — Those two are different faults, and it is the single most useful thing you can tell a technician.
Why the case stays on
Safety
Switch the oven off at the socket and unplug it. On a microwave the high-voltage section holds a charge in its capacitor after the power is off, and that charge is lethal. There is no owner-serviceable part inside the case and no safe way to establish that the capacitor has discharged without the right tool.
Models in the MM family
Reference| Model number | Family key |
|---|---|
| MM07V0W | avanti:microwave:mm |
When to call a technician
Call for anything that is not cleaning. The high-voltage capacitor inside can hold a lethal charge after the oven is unplugged, so there is no owner repair on this appliance beyond the cavity, the turntable and the door seal face.
Other MM problems we cover
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
