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Turbochef Subway toaster- F3 Mag, tested the orange wire and getting like 40 V.. 20 am fuse is hot to touch, already tried replacing fuse. How do I test diodes? Have only tested microwave diode.

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Posted on Jan 02, 2017

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  • 67 Answers

SOURCE: Neff combi blown diode.

If the diode failed by opening, there may be no other damage. If the dioded failed by shorting, the alternating current may have damaged other components. Ohm it out. You can get diodes from,, or radio shack or any electronics or appliance supply. If the diode is charred and you can't get the part number, the oven rating can be used to select a replacement. Since the fuse was 10 amps, the diode should also handle at least 10 amps. If you can power the unit and read the voltage at the diode input this will give you the power (volts times amps). It's always worth trying as it's cheaper than replacing the unit.

Posted on Nov 30, 2007

  • 1036 Answers

SOURCE: How to test a diode

To test a diode, first remove it, then use a test meter with a diode check facility. Test component first one way around, then the other. It should give a 1 in one position, and 0 in the other if all is ok.

This is the correct way to test a diode.

Posted on Jan 03, 2009

  • 9174 Answers

SOURCE: Kenmore microwave making loud buzzing sound.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

Posted on Mar 06, 2009

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SOURCE: No heat but everything else works

Sounds like the magnetron has failed. This is the component that produces the microwaves that heats the food.

The cost of the magnetron is about 95% of the cost of a microwave oven. Most people don't, for this reason, replace the magnetron, they replace the whole oven which is probably what you will end up doing.

There is a possibility that the circuit that provides power to the magnetron is faulty and you need to take it apart, find the proper electrical leads and test them with a volt meter. To do this you have to remove it from its mounting and take it apart. It is a fairly lengthy process however.


Posted on Apr 26, 2009

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SOURCE: Maytag MMV5156AAS Microwave won't heat and has hum/buzz.

A failed diode isn't the most common failure, but it happens. And sometimes it's due to bad magnetron or a bad connection.

If the capacitor fails, it almost always shorts, which results in a blown fuse whenever you hit "Start" to run the microwave.

The magnetron on this model should have a 5-year warranty, in case that's relevant. Your owner's manual is here.

We have the service / repair manual for this model and have uploaded it to our site here to help you.

It will give you safety info, step by step help in disassembly, troubleshooting tips, and part numbers.

Here are some links you or someone you know can use for test help, but read their safety warnings first:
(if it's not shorted or burned, it's probably okay)

There should also be 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.

You can find helpful exploded view diagrams and order parts here.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

Posted on Jun 30, 2009

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1 Answer

I have a kenmore microwave toaster. Microwave no heat. table rotates OK and toaster works OK. What is most likely problem, HV diode, capacitor or magnetron?

Could be any of those 3 parts since they work together to make the microwave part work. Most common problem if under 5 years old would be the diode, then capacitor, then mag, but I have replaced mags on new microwave in some cases. Like I said they work together. Capacitors will sometimes swell up at the top or bottom but again not always.. This isn't much help but you need a multimeter and must know some test procedures on this one.

Apr 14, 2015 | Kenmore Microwave Ovens


Troubleshooting KitchenAid oven, range and microwave error codes

Here list of Kitchen Aid range and oven codes.

4 Digit Failure Codes

F1 - E0 EEPROM communication error
F1 - E1 EEPROM checksum error
F1 - E2 UL A/D error
F1 - E4 Model ID error
F1 - E5 Calibration shifted
F1 - E6 Latch signal mismatch error
F1 - E9 Stack overflow
F1 - E3 Wiring harness cavity size does not match stored value
F2 - E0 Shorted touch pad
F2 - E1 Keypad cable connection error
F2 - E5 Cancel key drive line open
F2 - E6 Cancel key drive line open
F3 - E0 Oven temperature sensor (RTD) opened (upper oven on double oven models)
F3 - E1 Oven temperature sensor (RTD) shorted (upper oven on double oven models)
F3 - E2 Oven temperature is too high (Cook mode)
F3 - E3 Oven temperature is too high (Clean mode)
F3 - E4 Oven temperature sensor (RTD) opened (lower oven on double oven models)
F3 - E5 Oven temperature sensor (RTD) shorted (lower oven on double oven models)
F3 - E6 Drawer sensor open
F3 - E7 Warming drawer sensor shorted
F4 - E1 Meat probe malfunction - shorted
F5 - E0 Door Switch
F5 - E1 Self clean latch will not lock
F5 - E2 Latch during CLEAN error
F5 - E5 Self clean temperature not reached within 45 minutes.
F5 - E6 Door is open, but latch is locked
F5 - E7 Self clean latch will not unlock
F6 - E0 Return line not connected
F7 - E1 Common switch wire defective

Two digit codes:

F0 ERC Board failure
F1 ERC Board failure
F2 Oven temperature is too high
F3 Oven temperature sensor open
F4 Oven temperature sensor shorted
F5 ERC Board failure
F7 Function key stuck on ERC
F8 ERC Board failure
F9 Oven door lock failure

Microwave and Microwave combo error codes:

F1 - E3 or F1 - E4 Electronic control malfunction

F2 - E0 or F2 - E1 Keypad connection error

F2 - E3 Keypad held down too long, or keypad is shorted.

If you get an error code, try first resetting the code:
1. Disconnect power for about two minutes.
2. Connect back power.
3. If code re-appears, test and eventually replace faulty part.


on Mar 27, 2010 | KitchenAid KHMS155LSS 1000 Watts Microwave...

1 Answer

I have a GE profile XL Sensor VM 1350BW that will not go on fuse is ok, any suggestions? thank you

There are 2 thermal limit controls inside that if at any point the microwave got too hot they will go out like a fuse. One is mounted directly on the side of what is called the MAG TUBE directly behind the control panel. The second one is mounted against the cavity either on the left side or on the top middle. These are round thermal limits about the size of a dime with 2 wires attached to each one. Can't tell by looking at them if they are bad. Need an ohm meter to test. I usually jump the 2 wires together for a few seconds to see if if the microwave control panel lights up. If it does thats the bad one. You must replace the bad one since it is a safety feature.

Feb 27, 2015 | GE Microwave Ovens

1 Answer


Do you have Turbochef Tornado oven.
If yes then here is your solution.
Open right side pannel and check physically the transformers and the capacitors and the diods.
If you found burnt or burnt smell then replace that component followed by the replacing of the new fuse.
The fuse is located just under the magnetron cooling fan.(there were 3 fuse you need to replace the last fuse (facing oven from front and the last fuse 20 amps).

If you know to use DMM and clamp meter then reply me back I will give another solution .
please rate my work

Sep 20, 2011 | Microwave Ovens

1 Answer

I have Subway Microwave which just stopped no heat. some say that have to change Magnetron, but i am so sure. how and what should i do.

Take it to a repair shop if you are unsure about your abilities. First I would check the door switches and make sure those are all operating properly. There will be a cluster of small switches screwed onto a white panel. Make sure those are all operating correctly by doing a continuity check on each switch with the door open and closed and see if any of the switches are dead. Usually if the magnetron is bad it will draw a lot of power and kill the fuses. does the display power on? the magnetron is easily switched out on these microwaves. Its only 4 screws on the top and the mag will fall out swap the wires and you are good to go

Jun 09, 2011 | Amana RFS12MPS Microwave Oven

4 Answers

No heat

The service manual is here.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

Jan 29, 2010 | Amana RFS12MPS Microwave Oven

1 Answer

No heat subway microwave

what is the model number.. try to go to the brands website and locate a manual through there literaure dept or customer care sections..... why did u change the mag those are expensive? could be the fuse, therm,, rectifier thingie, or hi volt transformer, who knows call for service maybe.. depending how old it is i would tell you to just buy a new one

Jan 28, 2010 | Amana HDC12 Microwave Oven

2 Answers

Controlpanel flashes f 3

You have a faulty keypad. You could probably special order this part from a local appliance parts supply store for 50-60$ or purchase a new microwave.

Oct 22, 2009 | GE Spacemaker JVM1640SJ Microwave Oven

1 Answer

Microwave Oven

I report from owner manual.

F3 means : Short circuit on key panel (your touch pad).
You get F3 error if a shorted key panel is detected for more than 60 seconds.
Solution: . Replace key panel (touch pad).

Try first unpluggign power cord for five minutes.

If you think that the problem may had been caused by water inside the keypad you can try using an hairdryer on the keypad, taking care not to melt the keypad plastic.
If that does not work, then replace the keypad.

You can buy replacements here. or Order GE Microwave Ovens Parts Here

Mar 08, 2009 | GE JVM1630 Microwave Oven

3 Answers

Microwave sedems to be working but not heating

We woke up one morning and our microwave had no power. I checked the breaker and outlet they are working. Any help

Mar 23, 2008 | GE Spacemaker JVM1640SJ Microwave Oven

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