Microwave Light Not Working Due to Burnt-Out Bulb

The most likely cause for an inoperative light is a burnt-out filament. To confirm, unplug the unit, access the bulb compartment, and remove the bulb. Perform a visual inspection for a broken filament or glass discoloration. Use a multimeter in continuity mode; place the probes on the base contact and the side shell of the bulb. A reading of 'OL' (Open Loop) or no continuity confirms the bulb is burnt out and requires replacement.

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