56 replies to this topic

[yosemite]

I also have a Panasonic microwave that is approximately six years old - sorry I don't have the model number right now.  I had the exact same problem where the turntable would turn when I opened the door.  I brought it to a local shop that specializes in microwave repairs and they replaced one of the microswitches for the door.  If I remember correctly, he charged me $39 for the repair.  He knew right away what was wrong when I first called him.

[tpoindexter]

It's so easy a caveman could do it.

http://www.repaircli.../AMI2033/940337

 

 

if this problem always happens it should be easy to check the 3 micro switches with an ohm meter and know for sure what the problem is or is not

 

there are no shortcuts

 

 

I hate guessing

 

a multi meter takes the "guess " out of guesswork and leaves " work " 

 

I like "work"

 

get a ohm meter and check your door switches and "be sure"

 

 

My bets still on a bad door switch, most likely the lower switch, (probably the secondary switch), the primary - usually upper switch and the center/monitor switch will blow the fuse if they are not working in the correct sequence but I believe on some units if the lower switch has failed/welded contacts together then it can feed back thru the circuit and monitor switch to cause things like the turntable to turn and sometimes the cooling fan to come on when the door is opened.

[MrDave]

I really appreciate the replies. Now this is what it does:

I open the door, light is on, fan is off, turntable not turning (normal). Put something in it, close the door,

set the time, push start. Light comes on, turntable not turning, no fan, no magnetron running. counts down

for a few seconds and shuts off. Weird.

[Comstock_Services]

Not really sure what to say here, so I'll bite.

1. Do you have a multi-meter, Digital, or Analog does not matter.

2. Can you take the cover off of the outside of the microwave?

3. Can you then Locate the Wiring Diagram (inside of the outer cover, or near the control board)?

4. Take a picture of the diagram and share it on the forums! Help us help you!

[RegUS_PatOff]

.... Now this is what it does:

What did you change ?

[MrDave]

I actually did not change a darn thing. We have been using it (with the turntable turning when the door

is opened) and now it is acting like I stated in my previous post. I will as soon as I can, open the cover

and look for a wiring diagram. Yes, I will make sure it's unplugged when I do that. I am hoping it might be

something simple like a part replacement. I'm off work on Friday so I will be able to do it then. Please bear

with me as I trust all of you. Yes, I have a multi meter.

[NCARepair]

The lower door switch is burned. Look at where the contacts go into the switch body. Probably find it melted. Replace the switch.

[MrDave]

Okay, where can I find a source for a lower door switch? And what caused it to fail?

[tpoindexter]

It's so easy a caveman could do it.

http://www.repaircli.../AMI2033/940337

[NCARepair]

Try GE switch wb24x829. You should have a two terminal switch on yours which this is. Why did it fail? Like I tell my customers "you used it, it wore out." Actually therevis about 12-14 amps running through it and it gets hot and begins to melt the switch body. Good luck.

[MrDave]

To my dismay, I was unable to get the cover off. The torx screws on the back of the unit have

a little teat/stem in the center of the torx hole that prevent me from using any of my standard

torx drivers. I would need a torx driver with a hole in the end. The two screws in the side are

standard phillips, but that does me no good. Seems like Panasonic is making an attempt to

prevent end users from performing repairs on their own appliances. I suppose I could take

the torx driver to work and drill a small hole in the end of it so it would fit into the torx hole in

the screw. It's always something.

[RegUS_PatOff]

... I would need a torx driver with a hole in the end.

that would be a tamper-proof security Torx bit
hard to find


also used on some cable TV boxes .. but I can't talk about that ...

[MrDave]

I'll be damned....and there's a store about 3 miles away from me..........

(doo-dee-doo)

Thanks!

(it seems to never end)

Hah! You should hear my wife!......."Well, what about the microwave? is it fixed yet? What's the problem? How do I reheat my coffee? You said you were going to fix it!!!"

Geez......

[Budget Appliance Repair]

If you have a Harbor Freight store near-by they sale a security bit set for around $6.00 that as 5 or 6 security torx bits of different sizes and many other special security type bits.

 

The other option, (I've done this many times before I had the security bit set), just use a small screw driver and pop the little peg in the middle of the screw out.  They usually break off pretty easily.

[MrDave]

Okay, I watched the video on Repair Clinic on how to test the switch checking for continuity.

In laymans terms, before i depress the switch, should I see continuity? Should I see continuity

after i press the switch? Just asking because I want to definitely know if my switch has failed

or not. Basically, should I see resistance one way or the other? And which way? Geez.....

[MrDave]

Like I stated in my original post, I'm a machinist by trade, not an appliance repair guru, and I never

will say that I am. I'm not mechanically challenged by any means, but in an area that I am unfamiliar

with, I just need to be told or shown what to do, then all is good. So if I ask questions that to some of you

may seem a no brainer, once you show me, then I can proceed with confidence. I am very glad that i have

been getting the responses that I have seen, and I have to say....Thank you!!! Please bear with me until I fix this

damn thing. I will not give up easily. This microwave will not get the best of me. I will fix it with all your help.

Thanks.

MrDave

[RegUS_PatOff]

... I don't have a wiring diagram, and I would not know what to check or even what wires to check. Even if I did,

... I don't think I would know what to do with the results of testing the wires.

odd, for a (free) "Merit Apprentice" that somehow passed the Merit exam ...

Could have saved a lot of time (yours and ours) if basic testing / trouble-shooting was known.

We could post the wiring diagram, but I don't think it's a good idea for a "novice" to be working on a MicroWave,

with dangerous Microwave signals present if the Door Switches aren't working correctly,

OR if they aren't wired correctly.

AND high voltages present (even when turned OFF and un-plugged)

[MrDave]

I know basic electricity and am familiar with a multimeter. And I do understand that high voltages

are present even when turned off and unplugged. I'm not a dummy, and I do have a lot of

common sense. I can check things with a multimeter, but there are times that the result that

I would get when testing Would lead me to...(Now what does that result lead to?) That's

the thing. And I understand what you meant about working on a microwave.

No worries.

MrDave

[NCARepair]

Have you looked at the switch to see if it shows any sign of melting where the terminals go in?  Look closely.

[MrDave]

That's the first thing I will look at when I get the cover off. I might just pop those security tabs out of the torx screws

to get the cover off to check. I am growing weary of not having a microwave to use. When I get home from work every day

I'm pretty mentally beat up that all I want to do is relax a bit, eat dinner, then hit the sack. I do have a pretty good hunch that

the terminals will show signs of overheating. Also, to remove the switch, does it just pull off of the connectors, or what?

If the terminals do show signs of overheating, would it be useless to check for continuity? And if I do check it, what is the method

used to check it? What do I look for with the multimeter?

MrDave

Edited by MrDave, 21 February 2013 - 08:07 AM.