Asko Microwave SPARK Error: Sparking inside cavity
Asko microwave SPARK error is a common issue reported by Asko appliance owners. What SPARK Means on an Asko Microwave SPARK describes visible arcing or sparking inside the microwave cavity during operation. This is a high-severity fault that must not be ignored. While the most common cause — a metallic item left inside — is […]
No
DIY Fixable
From $140
Typical Repair Cost
30-60 min
Pro Repair Time
Quick Assessment
Answer to continue safely
Is it safe to keep using?
No. Stop using the microwave immediately when sparking occurs. Continued operation risks cavity fire, magnetron damage, and permanent appliance failure. Identify and resolve the cause before any further use.
Can I reset the code?
No. Sparking is caused by a physical condition (metal, damaged cover, food residue). These must be physically corrected — a power-cycle will not resolve the fault.
When to stop immediately?
Stop if you notice: Any sparking or arcing observed inside the cavity — stop immediately and unplug., Smoke or fire visible inside the cavity — do not open the door; unplug and call emergency services if fire persists..
Symptoms You May Notice
Visible sparks or blue-white flashing inside cavity
Bright flashing arcs are visible through the door window during operation, sometimes accompanied by a crackling or popping sound.
Burning smell from inside the cavity
An acrid burning odour accompanies or follows the sparking, indicating carbonised food residue or a scorched waveguide cover.
Black or brown scorch marks on cavity wall
After sparking, dark scorch marks or pitting are visible on the interior walls, confirming arcing has occurred at that point.
Popping or crackling sounds without visible sparks
Audible popping during operation without a visible arc can indicate internal arcing at the waveguide or within the magnetron assembly.
Possible Causes
Metal or metallic-trim item in cavity
Any metallic object concentrates microwave energy into an arc. Gold or silver trim on plates is a frequent overlooked cause.
DIY PossibleDamaged or burnt waveguide cover
The mica waveguide cover absorbs splattered food and can develop conductive carbonised spots that arc during operation.
DIY PossibleCarbonised food residue on cavity walls
Heavy food deposits on the walls concentrate microwave energy and arc in the same way as metal objects.
DIY PossibleSafe Checks You Can Do
-
1
Stop operation and remove all metallic items
Unplug the microwave. Open the door and confirm there is no foil, metal utensil, or metallic-trim dishware inside the cavity. Remove everything and inspect carefully.
Twist ties on bread bags and metallic patterns on paper plates are easily missed — always use microwave-safe containers.
-
2
Inspect and replace the waveguide cover
Locate the flat rectangular panel on the interior wall (usually right side). If it has scorch marks, holes, or brittle crumbling edges, remove it and fit a replacement. Clean the wall behind it.
Replacement mica waveguide covers can be cut to size from a sheet if an exact part is unavailable — ensure no gaps around the edges.
-
3
Deep-clean the cavity
With the microwave unplugged, steam-clean or wipe all interior surfaces using a microwave-safe cleaner. Pay particular attention to the roof and corners where splatter accumulates.
Placing a bowl of water with lemon juice on high power for 3 minutes loosens baked-on residue, making cleaning easier.
When to Call a Professional
Contact a qualified technician if:
- Sparking persists after all metal items are removed and the waveguide cover is replaced.
- Pitting or burn marks are present on the cavity walls themselves rather than the cover.
- Microwave produces a burning electrical smell even with an empty, clean cavity.
Need Professional Help?
Find qualified technicians in your area for proper diagnostics and repair.
Microwave Repair Service Schedule Appointment