Microwave fan and light come on as soon as the door is closed, or the unit attempts to run with the door open.
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Danger: A microwave that runs with the door open is extremely hazardous. Immediately unplug the appliance and do not use it until repaired.
User-level action:
- 1. Disconnect from power: Unplug the microwave and keep it unplugged. Do not attempt to operate it again.
Technician-level checks:
- 2. Inspect door switch wiring: Verify that the primary, secondary, and monitor switches are wired according to the Sage wiring diagram. Correct any miswiring.
- 3. Test switches: Check each door switch for proper operation and ensure contacts are not welded closed.
- 4. Check control relays: Inspect the control PCB for stuck or welded relays that may be supplying power when not commanded.
This condition must be corrected by a professional. Do not bypass safety circuits.
Repair Difficulty
Required Part
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