Difficulty cleaning Electrolux High Speed Oven

Failure should be found in the high voltage section of microwave oven.
Magnetron, HV capacitor, HV diode or HV fuse, tranformer HV secondary coil

Dado

Sometimes a door latch or magnet closure is a problem. If the door fails to make proper contact when closed, the oven will not start. If the oven goes on and off, there is a disconnect and in some cases the rotating glass dish inside vibrates and causes a disconnect also.

Hello - Interior cleaning after convection, mix or broil cooking:

Spatters may occur because of moisture and grease. Wash immediately after use with hot, soapy water. Rinse and polish dry. Harder to remove spatters may occur if oven is not thoroughly cleaned or if there is long time/high temperature cooking. If so, you may wish to purchase an oven cleaner pad with liquid cleaner within it-not a soap filled steel pad-for use on stainlessor porcelain surfaces. Follow manufacturer's directions carefully and be especially cautious not to get any of the liquid cleaner in the perforations on the wall or ceiling or any door surfaces. Rinse thoroughly and polish dry. After cleaning the interior thoroughly, residual grease may be removed from the interior ducts and heater by simply operating the oven on 450 F for 20 minutes without food. Ventilate the room if necessary.

Interior cleaning after microwave cooking:

Cleaning is easy because no heat is generated to the interior surfaces; therefore, there is no baking and setting of spills or spattering. To clean the interior surfaces, wipe with a soft cloth and warm water. DO NOT USE ABRASIVE OR HARSH CLEANERS OR SCOURING PADS. For heavier soil, use baking soda or a mild soap; rinse thoroughly with hot water. NEVER SPRAY OVEN CLEANERS DIRECTLY ONTO ANY PART OF THE CONVECTION MICROWAVE OVEN.

The buzzer on the keypad control has opened, or one wire has come off due to poor soldering, or the voltage to the buzzer is missing.

There are three common issues, magnetron "heats food" cracked high voltage diode, or a shorted high voltage capacitor. In order to find out you will need a professional to assess, it will be probably cheaper to replace the microwave oven.

Oven installer first due, to the difficulty of making electrical and, or, gas connections if the top of the island in enclosed first.

Most likely needs a new magnetron

It looks like the part of your computer board on microwave which responsible for controlling light and fan stop working. In this case you have to replace computer board.

I’m happy to help further over the phone at https://www.6ya.com/expert/vitaliy_f406165329c75ede

The question is... Do you want to put money on a 18year MW, or put it towards a new one? I must admit I love the SHARP Combo MW Convection ovens. I own two. One is almost 25years old. The mechanical Timer Type, but they work great and I can maintain them with 30years ef exrerience. I am now retired.
It does sound like the Magnetronhas broken down, however it could be other things in the Secondary (High Voltage Side). The High Voltage Side is made up of the Secondary HV side of the High Voltage Transformer, A High Voltage Diode, a High Voltage Capacitor, and the Magnetron. The High Voltage Side is DANGEROUS, and CAUTION should be taken to protect yourself against EXTREME HIGH VOLTAGE. unplug from power and DISCHARGE High Voltage Capaciton to frame GROUND before touching anything!!!!