Microwave stops immediately when START is pressed, or stops mid-cycle when the door is slightly touched; sometimes accompanied by a door error beep.

Safety warning: Always unplug the microwave and allow several minutes for internal capacitors to discharge before opening the cabinet. High voltage inside can be lethal.

Steps to diagnose secondary and monitor switches:

• 1. Check door alignment: With the door closed, check that the gaps around the door are even and the door sits flush with the cabinet. If the door is sagging, gently lift it while closing to see if the symptom changes. Sagging indicates hinge or latch misalignment.
• 2. Inspect latch hooks: Look for worn or cracked plastic hooks on the door. If they are rounded off or loose, they may not fully actuate the switches.
• 3. Remove outer cover: With the unit unplugged, remove the screws securing the outer case and slide it back and off. Keep clear of the high-voltage section.
• 4. Locate switch stack: Identify the group of 2–3 microswitches mounted near the door latch. They are usually labeled or wired in a cluster.
• 5. Test each switch: Using a multimeter, test continuity between COM and NO/NC terminals while manually pressing the switch actuator. Compare readings with the switch markings (NO should close when pressed; NC should open). Replace any switch that does not change state cleanly.
• 6. Check bracket and screws: Ensure the switch mounting bracket is not bent and all screws are tight. A loose bracket can cause intermittent door errors.
• 7. Replace faulty switches: Install Sage-compatible door interlock/monitor switches, transferring wires one at a time to avoid miswiring. Ensure actuators line up with the latch cams.
• 8. Reassemble and test: Refit the cover, plug in, and test by gently wiggling the door during operation (without opening). The unit should not stop unless the door is opened.

If the error persists, the control PCB door-sense circuit may be faulty and should be evaluated by a technician.