The short answer
On the Black Decker BDMW microwave an electrical complaint is usually arcing inside the cavity rather than a fault in the wiring. The BDMW stems step through sizes on a common mechanism, so the checks below hold across the model list — and all of them stay outside the cabinet.
What you observe
- Sparking or a flickering blue glow inside the cavity — Arcing.
- The breaker or a protective device trips when the oven runs — A load fault or a shared circuit.
- A hot plug or a warm cord — Resistance at a connection, and the one symptom on this page that is about the outlet rather than the appliance.
- NEAR MISS — a loud hum with normal heating — Many ovens are simply loud under load.
Causes, most likely first on the BDMW family
- Metal in the cavity and metallic trim on dishes — First on this family — the BDMW stems step through sizes on a common mechanism — and a small cavity brings everything close to the walls: a fork left in a bowl, a tie, a gold rim on a plate, or foil folded against a wall arcs immediately and alarmingly.
- A soiled or damaged cover over the waveguide opening — Second: baked-on grease on that cover chars, and charred material arcs. It is the most common genuine cause of sparking in an oven that has been in daily use.
- Damage to the cavity paint or the walls — Third: once the coating is broken and rust has started, the exposed metal arcs at the same spot every time. It shows as a repeatable burn mark in one place.
- Internal high-voltage faults — Last, and entirely off-limits: a fault in the cabinet announces itself with tripping, smell or noise rather than with a spark in the cavity, and nothing about it is owner work.
Check in this order, and why
- Stop, unplug, and look at what was in the cavity — First because it is free and because the answer is usually sitting on the turntable: metal, foil, or a dish with a metallic rim.
- Inspect the cover over the waveguide opening — Second: charring or a hole there explains repeat sparking, and the cover is a consumable rather than a repair.
- Look for a burn mark that appears in the same place — Third — a repeatable spot means cavity damage rather than something in the load.
- Note whether anything trips or smells — Last of the owner checks, and the point at which this stops being a cleaning job.
Before you open anything
Safety
Unplug the oven before touching anything beyond the cavity and the door — and then still do not open the cabinet: the high-voltage capacitor inside can hold a lethal charge long after the oven is disconnected, which makes this the one kitchen appliance that can injure you after it is switched off. Never tape, wedge or otherwise defeat a door interlock, never run the oven empty, and stop using it altogether if the door, its inner panel or its mesh is bent, cracked or burned.
Models in the BDMW family
Reference| Model number | Family key |
|---|---|
| BDMW0107CB | black-decker:microwave:bdmw |
| BDMW0107CS | black-decker:microwave:bdmw |
| BDMW0107CW | black-decker:microwave:bdmw |
| BDMW0109S | black-decker:microwave:bdmw |
| BDMW0111S | black-decker:microwave:bdmw |
When to call a technician
Call, or replace the oven, if it trips a breaker on a circuit with nothing else on it, if there is a burning smell with a clean cavity and clear vents, or if sparking repeats in the same place with nothing metallic in the load. Call an electrician rather than an appliance technician if the plug or outlet is hot — that fault is in the wall, not the oven.
Other faults covered for the BDMW family
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