Any thoughts on a dead unit. Does not power up. Already checked power in on cord, internal fuses. power transformer, etc., all ok. Can you tell me common component failures for this problem?

There might well be a fuse. Look around the area where the power cord goes in and around the transformer.

All microwaves has both internal thermal cut out and internal fuse, Yours problem sounds like an open 9 volts transformer that power up the front panel

NAD M15

Problem : Dead


Possible solution : Check for Power Supply

How to Test a Transformer: 7 steps - wikiHow


If these has been done,


• Check amp power supply and low voltage regulators

These includes fuses ( many of them )



Tech Center tells you how to use a multimeter .

• There could be other electronic components but try on them first.


If the torroidal transformer is OK , then it could be a problem on the

Circuit boards.

There could be a shorted components somewhere.

Hi terry,
Try to check the power cord, it might be open due to frequent bending or pulling. If you confirmed that the power cord is ok then the trouble now is the ff :
1. Internal fuse
2. Thermal fuse of the transformer - If your transformer is open primary winding, check it inside the transformer. This is placed inside the paper insulator.
If you don't have an experienced in electronics then I've advice you to look for a qualified technician to isolate the problem.
Hope it may help you.
Have a nice day!
JDVillanueva

check power between power cord connection and inernal fuse,start at cord connection and work way to fuse conn.eliminating possibe problem area

Your unit is dead, mains are good, tried in other receptacles, still no power. You have a bad fuse inside the unit. Unplug. Remove the cover. Generally this requires removing all the screws on the back perimeter and lifting the cover up. Sometimes they stick due to old grease, etc. Somewhere in the area of where the power cord comes in or near the transformer there should be a small fuse in a holder. It is not a glass fuse and should be replaced with the same kind (ceramic) and value. This is important for future protection. You can get the fuse at www.mcmelectronics.com . Get a box of five for future problems. If this was the only problem your microwave should work. If it blows the new fuse you could have a shorted power transformer, bad high voltage diode, or a bad magnatron in that order. There could also be a short in the board with the display but that would be unusual. Let me know if you need anymore helpl

hardrocko

Thanks for using FixYa

The standby light should be on. If it is not, then check the main fuse. WIth the unit unplugged, remmove hte top cover and check the fuse by the line cord. If that is ok, then you will need to check the primary winding on the standby transformer. That transformer has a thermal fuse internally located and that sometimes gets blown due to a power surge. If you do not have the equipment to test this, get a detailed estimate from a local servicer. The standby transformer usually costs arounf $25 or so.

Dan

do you get any error message ?

Most microwave ovens are equipped with an internal fuse. This is typically located where the power cord enters the cabinet. The cabinet will have to be opened to verify the fuse.

The magnetron is not directly attached to the power source, it has to be stepped up in voltage significantly, either through a transformer or inverter.

It is usually best to have professional tech check the fuse for operation. Most shops will do this for a small fee if you drop the unit off yourself.

That's interesting.. After researching that model I can tell you that it has an intergrated internal power supply(transformer) which does contain a fuse. It is located where your power cord plugs into, inside the unit, start with that. Was it plugged into a surge protector? When you had the power failure the second time was there a fluctuation of power, ie your lights in your house flickering on or off or increasing, decreasing in brightness? This will help me determine if it's something else. Also be sure to check your power cord, look for any kinks, breaks, chips in insulation. Anyway Good Luck