📡 Microwave not heating
TechnicianStep-by-step troubleshooting guide — 5 steps, Microwave, Technician difficulty.
⚠️ Common Causes
Magnetron failed, high voltage diode failed, high voltage capacitor discharged, turntable motor running but no heat
🔧 Parts to Check
- Magnetron
- Hv diode
- Hv capacitor
- Door switches
🔧 Troubleshooting Steps
- ⚠ SAFETY: Unplug microwave before any work. HV capacitor can hold lethal charge even when unplugged!
✓ Expected: Unplugged and discharged
- Test door switches — microwave will not fire if any door switch is open. Test for continuity when pressed
✓ Expected: 0Ω when switch pressed
- Test high voltage diode — set multimeter to diode mode. Should read one direction only (not open both ways, not shorted)
✓ Expected: Diode reading one direction
- Test magnetron filament — should read 1-3Ω. If open (OL), magnetron is dead
✓ Expected: 1-3Ω
- Check fuse — most microwaves have a thermal fuse on the magnetron. Test for continuity
✓ Expected: 0Ω