Sparking inside the microwave.
That is a stop-what-you're-doing moment.
But here is the thing. Most microwave problems, sparks included, come down to one cheap part. Under $50 in most cases. Don't bin the microwave yet.
This guide matches every common microwave symptom to the part causing it. Browse the full microwave parts range once you know what you need.
What Is Your Microwave Actually Doing? Use This to Diagnose It
Don't guess. Match the symptom to the cause first.
It runs but the food stays cold
Magnetron failure. Or a blown diode. Or the door switch.
Start with the door switch ($20–$40). Cheapest to test. If that is fine, magnetron failure is next. Magnetrons cost $80–$150 and signal end of life for older units.
Turntable will not spin
Either the motor is dead or the plastic coupler under the plate has snapped.
Both are easy fixes. No tools. Under $45 total.
Sparks inside the cavity
Stop. Seriously, stop using it right now.
The waveguide cover (a thin mica sheet on the cavity wall) has burned through from food splatter. Replace it before you run it again. Continued sparking can destroy the magnetron, which turns a $15 fix into a $150 one.
No interior light
The bulb is blown. Quick swap. Different models use different bulb sizes, so check your model number first.
Loud buzzing noise
Buzzing with no heat? Magnetron failure.
Buzzing but food is heating? Could be the turntable motor struggling.
Brand-by-Brand: What NZ Microwaves Need Most
Brand matters. Parts do not cross over between brands. Here is what sells most for each brand on our microwave parts page.
Panasonic
The F20559Y00AP mica waveguide cover fits a wide range of NN-SD and NN-ST models. Most-replaced Panasonic part in NZ. The F06015Q00AP glass plate and F612E9V00XP lamp holder follow closely.
Samsung
Roller rings and turntable motors go most often. Control panel buttons also wear out after years of splatter build-up.
Breville
315mm glass turntable plates. That is the big one. They crack from temperature shock and drops. Roller rings are second.
LG
Waveguide covers and turntable couplers lead the list on LG microwaves.
Replacing Your Glass Turntable Plate: 3 Minutes
Unplug the microwave. Open the door. Lift the plate straight up. Remove the roller ring underneath. Wipe the floor and motor coupler. Drop the new roller ring in. Place the new plate on top and lock it onto the coupler.
Run a 30-second test with a glass of water inside. Done.
No tools. No warranty voids. No drama.
Repair or Replace? The Real Maths
Under 8 years old and one part failed? Repair it. Every single time.
Over 8 years old and the magnetron is gone? Replacement might make more sense. A magnetron alone is $80–$150 before labour.
Cracked plate? $20–$50. Burned waveguide cover? Under $25. Always fix those.
Frequently Asked Questions
Where is my microwave model number?
Inside the door frame on most models. Also check the back panel. Got the number? Search the microwave parts collection from there.
Can I replace the glass plate myself?
Yes. It is the easiest appliance repair there is. Most NZ microwaves use 245mm, 270mm, 315mm, or 345mm plates. Match the size, swap it in. Done.
Why is my microwave sparking?
Burned waveguide cover. Stop using it until you replace that part. Running with a burned cover can destroy the magnetron and turn a $15 fix into a $150 one.
How long should a microwave last in NZ?
8 to 10 years for everyday household use. Coastal areas like Auckland and Wellington can see faster internal condensation build-up, which may shorten that slightly.
The Bottom Line
Most microwave fixes cost less than $50. The machine works fine. One part doesn't.
Find the part. Fix it. Keep cooking.
Ready? Browse microwave parts.
Can't find your part? Email steve@appliancespares.nz with your model number.