NFFF C57MONOGB OVEN SWITCHES OFF THEN CODE E305 SHOWS when IN MICRO MODE

R-9H84B - May 29, 2017

I would suggest pulling the control board out and looking on the foil side (opposite the component side) for "ring cracks," most likely on the low voltage transformer's connections.

The board may have the screen-printed reference designator "T1" near the low voltage transformer.




Also be sure the fuse is not easy to turn with your fingertips when it is in the holder. If it is, the fuse holder is too loose and must be replaced (not just squeezed with pliers).

You can order a fuse holder, part number WB06X10034 for $6.49 (subject to change) from the Pros here.

If you have any keypad issues, please note that the membrane keypads for this model have long been discontinued.

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- William E. Miller, AS-EET
[email protected]
http://www.microwavecontrol.com
Microwave Oven Control Panel Repair Nationwide
"Recycling by repairing since 1982"

Most microwave ovens have up to 4 micro switches in the door latch, it's a safety interlock. These can go bad, and cause the oven to not function.
Micro switches are pretty inexpensive, and can be replaced. You need to open the oven, and then identify exactly which micro switches you need. Both my current microwave ovens have done this, and I've replaced the bad switches. They work fine now.

one or more of the door micro switches are open or shorted..the micro switches tell the unit the door is closed and safe to use.the micro switched are marked normally open or closed..take note when replaceing them..also their is a actuator lever that tells the switch to close or open..it is plastic and connected to the door latch..it can be broken off or bent from heat,,its plastic..make sure its in place and working the micro switch

Be-safe, Un-plug your microwave oven ,

Open the microwave cover ,
Close and open door few times to check the door latch(es) and switch(es).
Door switch assembly may has one or more micro switches.( Most switches are black or grey and about 1,25 in long X 3/4 in wide X 5/6 in thick with two or three wire connections).
Making sure door latch close and open these micro-switches.

You can hear the switch "clicks" when small switch pin or lever is pressed.

Sometime these door micro-switches pin or lever get stuck or broken.

You can take couple pictures before remove wires or micro switches

You can buy these switches for about 3-7 dollars online. Some web sites have video showing how to check them. (Using Volt-Ohm meter)

One of the micro switches in the door is stuck ( faulty ) there are normally 3 switches so after removing the lid open and close the door and you will see the door latches pressing in the button of the micro switch and one of them would indicate that one of the switches is not in line with the latch to press the button in or one of the micro switches has melted inside cosign the switch to release normally open or normally closed, you need a multimeter to test the switches in that case

(Fuse is a ceramic fast blow 20A Little Fuse 0314020 or Eton ABC-20) Melting I²t 631
If the Fuse blows when the door is opened. (not even energizing the microwave) The bottom micro switch (monitor micro switch) is normally closed, (open when the door is closed) however if it remains in the closed state when the door is open you will have a short circuit with the Primary Micro switch. The circuit diagram shows that one of the two switches must be open. I was able to test with an ohm meter. With a bad switch the reading was less than an ohm with the door open and 290 ohms with the door closed - Across the plug with a good fuse. With the new micro switch the resistance shouldn't change by much with the door open or closed.

Check the door safety interlock switches ... tiny micro switches found near the latch mech inside the cabinet.

If they are faulty, the oven thinks the door is open and will not turn on the 'heat' in microwave mode.

Thank you for your question @ FixYa.com

Check the door safety interlock micro switches. Others will po9int to the very expensive magnetron and it might be that but I don't think so. Still others will tell you that it is the capacitor ... and it might be that. If you regularly open the door while the oven is operating, the tiny contacts become damaged from the arcing. When the interlock switches can not longer tell the oven the door is in fact closed, the magnetron will not come on .. and there will be no heat.

It is probably worth removing the cover to check the $2.99 micro switches ...

Make sense?

Thanks for your question @ FixYa.com

either you have a fuse in the cavity blown or you have a failure in micro switches, this is the only way this comes up

Sounds like you should get estimates and turn in on homeowners insurance. Power surges are very destructive and you have lost the control board at least and maybe some switches. Eric