MyJMV8208 Jenn-Air microwave will not heat. How do I check the Fuse? thermal cutoffswitch? or...where are they

Hello, Sounds like the transformer may have problems. There are very high voltages even in a microwave that is not powered up. Be carefull. It is between to take into a shop to have repaired.

The thermal fuse monitors the magnetron temperature and cuts power, if it gets to hot and resets in no more than 20 to 30 minutes. Unplug microwave oven, remove top, "several screws" look over to the right, thermal fuse is mounted on top on the inner chassis, "round and thick with 2 wires clipped on"

Hi!
I read your comment about needing to remove the control board to inspect it for damage. Looking at the diag. below, all you need to do is open the oven door and remove the two screws (#2 on diag.) fastening the brackets that hold the board in place and you can take it from there.

Refer to the diag. below If it was me, I would start by turning the breakers for both ovens OFF, then, in getting someone to help me pull the oven out, disconnect the power cord and check the power circuit protection devices like the fuse #4, located above the fan and the power board #25 also located on the back of the unit. Before replacing the blown fuse, inspect the wiring, If the unit is mounted over an oven that was in the Self Cleaning Mode that reaches temps. of about 500 degrees, there is a chance that a wire's insulation melted and shorted the unit.


If you need better resolution and the names and prices of the components on these diagrams, click on the following links: for the first diag: http://www.searspartsdirect.com/partsdirect/part-model/Jenn-air-Parts/Microwave-Parts/Model-JMC8130DDB/1266/0123100/M0512405/00001?blt=06&prst=0&shdMod=JMC8130DDB for the second diag: http://www.searspartsdirect.com/partsdirect/part-model/Jenn-air-Parts/Microwave-Parts/Model-JMC8130DDB/1266/0123100/M0512405/00004?blt=06&prst=0&shdMod=JMC8130DDB
I hope this info is helpful to you. If you need further assistance, just place a comment.

there is on some Models fuses that can be replaced and or an Thermal fuse blown , got too hot and shut down the heating element , both can be purchased @ Radio Shack , Thermal fuse rated @ 8-10 amps for a few dollars . . and can be crimped on or soldered inline. hope this works for you ? good luck >

Have you check the thermal cut off switch?

For future reference, I always recommend that you turn on the microwave's hood vent exhaust fan whenever you're cooking on the stovetop or oven.

Depending on the brand and model, there will be either a thermal cutout or thermostat on or near the magnetron. There is also one on top of the oven chassis ceiling, but under the outer cover.

Either device may have opened.

In many brands there is a "mini-manual" (tech sheet) hidden inside the unit behind the control panel or hidden on the left side behind the grille, which is very helpful when troubleshooting, testing, and locating components.

At our Web site, we have a video available showing how to remove a typical over the range control panel assembly in under 5 minutes.

Accessing some components (especially the oven cavity thermostat / thermal cutout) for testing and possible replacement will require you to remove the oven from the wall.

If so, the installation instructions are very handy, and it's best to have two people since the microwave can be heavy and awkward.

You can download GE owner's manuals and installation instructions here.

You can download owner's manuals and installation instructions for several brands (including Amana, Frigidaire, Jenn-Air, Kitchenaid, Litton, Maytag, Roper, Tappan, Thermador and Whirlpool) here.
You can find links to helpful exploded view diagrams and part ordering help here.

I recommend that you bookmark that link to your favorites.We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer

If everything works but the heat, its probably a blown thermal fuse, could be blown fuse for the HV transformer, bad connection to magnetron filament, or several other things. You will have to take the microwave apart, several screws around the cabinet make sure you know where each screw goes back because they all may not be the same. andbe very careful even with it unplugged there is high voltage present at the capacitor.

Look for a reset button on the back--push to reset. If trips again, unit has probable short.

Took microwave out, opened back, 15amp fuse blown. Replaced all ok.

Heating element or capacitor fuse