The short answer for this family
On the Criterion TM microwave family an electrical symptom is the one class of fault where the right first action is not a diagnosis: unplug the oven and stop using it. A microwave holds a high-voltage capacitor that can retain a lethal charge after the power is off, so everything past the outlet is a technician job. The spine carries a single model number here.
What you observe on these models
- A tingle or shock from the case or the handle — Stop immediately and leave it unplugged. A shock from an appliance case is an earthing fault and it is dangerous regardless of how small it felt.
- The plug, cord or outlet is hot or discoloured — A loose or failing connection heating up under load. This is a wiring fault at the outlet as often as an appliance fault, and both need attention.
- The breaker trips when the oven starts cooking — A real electrical fault or a badly shared circuit. A standard household branch circuit is rated 15 A or 20 A, and a microwave is one of the heaviest loads in a kitchen.
- NEAR MISS: the oven simply will not start — A refusal with no smell, no spark and no trip is a door or lock fault rather than an electrical one. Read the page for an oven that will not start.
Causes, most likely first on this platform
- Metal or foil in the cavity, or a damaged waveguide cover — First because it is the most common and the most preventable: foil, a metal-trimmed dish, or a carbonised waveguide cover all arc. The cover is a consumable part and it is the one to look at after any arcing.
- The circuit is shared, extended or undersized — Second: a microwave on an extension lead or sharing a circuit with another heavy load trips breakers and overheats connections without anything inside the oven being faulty.
- The cord, plug or outlet is damaged or loose — A hot or discoloured plug is a failing connection, and it is a fire risk in its own right. This is checked before anything inside the appliance because it is visible and common.
- A high-voltage component has failed short — A breaker that trips the moment cooking starts points here: the transformer, diode or capacitor has failed in a way that loads the circuit. It is not an owner part and not an owner diagnosis.
What to check first, and why in this order
- Unplug the oven before anything else — This is the only diagnostic page here that starts with stopping. Arcing, tripping, shocks and burning smells all justify pulling the plug first and thinking afterwards. Work down in order rather than jumping to the likeliest cause.
- Look into the cavity for metal and for burn marks — Foil, a metal-trimmed plate, or a burnt patch on the waveguide cover in the cavity wall. Most arcing is answered at this step.
- Check the plug, the cord and the outlet — Warmth, discolouration or a loose fit at the outlet is a failing connection. Do not keep using the outlet while you decide.
- Establish what else is on the circuit — A microwave belongs on its own outlet, not on an extension lead and not sharing with another heavy appliance. This alone resolves many tripping complaints.
Before you open anything
Safety
Unplug the oven at the first sign of arcing, a burning smell, a shock or a repeated breaker trip, and leave it unplugged. Do not remove the outer case: the high-voltage capacitor can retain a lethal charge long after the oven is disconnected, and discharging it is a trade procedure. Never run a microwave empty, never put metal or foil in the cavity, and never run one on an extension lead. A standard household branch circuit is rated 15 A or 20 A, and a breaker that trips again is reporting a fault rather than being a nuisance.
Models in the TM family
Reference| Model number | Family key |
|---|---|
| TM034K6LP-P0HA00 | criterion:microwave:tm |
When this stops being owner work
Looking in the cavity, checking the plug and outlet and sorting out what shares the circuit are owner work. Everything else here is a call, and in several of these cases it is an electrician rather than an appliance technician: a hot outlet, a tingle from the case or a breaker that trips with other appliances too are wiring questions. On this platform this oven is bolted to the wall and the upper cabinet and is heavy enough that taking it down is a two-person job before any repair begins.
Other faults on these models
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
