ACO1840AW - Overview

The nightmare was that this microwave is installed under the cabinet....in order to get to the light bulb I had to pull out my stove then squeeze into the space between the stove and counter....my old microwave light bult was much easier to change.....Shame on Whirlpool for making this so difficult.....must be a better way to cover the light bulb so that we do not need a screwdriver to remove the door to get to the light bulb

1. I went to the internet to find the service manual for the Maytag microwave.
2. I opened up the oven and started measuring the resistance of the diode, capacitor, transformer, and magnetron between terminals and then to ground. The transformer and magnetron were well within the resistance limits. The diode was shorted in both directions(+-). The capacitor was fully open in both directions -- high resistance.
3. I ordered the 2 parts, installed them, and ran the oven. Worked perfect first time.
4. Reinstalled oven and worked ever since (1 week so far).
5. The secret was that the transformer had a load hum. I figured the transformer was OK. The magnetron had no short between filaments and ground to filaments. The only two left were the diode and capacitor. The first two are about $200 -- almost the value of a new microwave. The $70 repair was well worth it. If the first two were still bad, then tempted to buy a new oven.

Removed 1 screw, removed "burnt out" bulb and replaced it with new bulb.