Saturday, 31 March 2012

Pansaonic inverter microwave cuts out, stops, resets: 2M236-M42 NN-A713a

This microwave was not heating food, cutting out after about 10 - 20 seconds.

Trying to use it, all would sound normal for a couple of seconds but then there was a buzzing arcing sound and relays would start to click and finally the microwave would stop and the timer reset itself.

There was some information on the web about Panasonic microwaves showing error codes but it was showing nothing after it cut out.

The microwave was opened up and (carefully) run with the cover off to see if the arcing was visible, possibly see something else ? On initial inspection nothing could be seen, just the original symptoms heard.

The microwave lamp comes on with the power and was making it hard to what may have been arcing so that was disconnected.

I still couldn't see anything so decided to power off and just have a look at the magnetron, there was talk on the web of seeing the magnet had cracked, I could measure the filament too.

Well upon removal I was a bit shocked, the side of the magnetron that could not be seen with it in place looked like this....

Hmm, that doesn't look right ! It looks like it got a bit hot !

Inspecting the rear air vent it was totally blocked with grease and fluff. The picture is after I started to clean it.

So a new magnetron was ordered off ebay, only £28 (cheapest local shop wanted £60).

Here it is next to the old one. All the adverts on ebay say the new one is a genuine Panasonic item sourced from Panasonic direct, just not branded because they are used in many brands of microwave for rivals ? No way to be sure.

In it went and all working again. :-)


  1. Thanks for this. I am about to perform the same process on a very similar cooker (9 years old, not too bad) having ordered one from eBay. Mine is thoroughly cracked and there was a serious smell of electrical cooking going on so I am hoping that the HV PSU is still alive.

    Fixya also has a few tips.

    I find it very disappointing that people like Panasonic make so little effort to engage with customer support like this on the internet - although maybe encouraging the punters to mess with Microwave innards would give H&S heart failure, and help fill up the various Darwin homage sites?

    Panasonic is not the worst for customer support - Acer is utterly contemptuous of its customers, and I will never ever buy another Acer product after eventually being quoted more for a replacement LCD monitor PSU than a complete new 28" Hanns-G cost.

  2. Thanks for your blog post, I was starting to think no-one cared! I have no idea about electrics or engineering or anything like that being a typical girl but I'm willing to learn if it means saving money in the future, another past-time of mine weirdly enough. I've bookmarked the forum in my 'Peugeot' folder on Google Chrome (nice and organised!). I have no idea what a cam belt is but apparently it's expensive? Any way of doing this for cheap? Love the Haynes manual translation btw! Is it purely for laughs or am I meant to take it seriously?

  3. Thanks for a great article, fixed mine for £26.58, details below:-

    Panasonic 2M236-M42 magnetron for Panasonic inverter microwave ovens
    Sold by Top Spares
    Condition: new
    Item Subtotal: £21.99
    Delivery & Handling: £4.59
    Total before VAT: £26.58
    Total: £26.58

  4. i like your post its very informative. keep sahring more.
    12v dc inverter

  5. This comment has been removed by a blog administrator.

  6. We are having this problem and I think it is just easier to buy a new (cheaper) microwave....

  7. Old design. Insufficient tracks clearances under side of inverter board. Wipe clean with meths especially if heat grease has leaked.
    Second visit of this problem on one oven.
    Almost five years return.
    Unplugged the inverter type oven is safe. I think.
    Not worth commercial repair. Very few are shops trust worthy and Panasonic are generally unhelpful so consider a replacement. This is a throw away if the clean no good.

  8. Ours got very hot last night and cut off after 5 seconds of cooking consistently, even after it cooled down. The magnetron is in the exact area that was very hot, so I think I will be checking this out later on this evening. Thanks very much for this, very useful!!

  9. Ours cut out then when I opened the door it started . Yes , that's right it started with the door open as if opening the door was the starter.

    1. Its' probably a bit late now but the door interlock assembly can work it's way backwards. Open door, slacken the upper and lower mounting screws one full turn ( 360 degrees ), push the assembly towards the frame and hold firmly while retightening the screws ( firmly hand tight, carefully, as they are into plastic and can strip ). Check the bulb as the misalignment can cause it to blow.

  10. Ours is doing this, but the Magnetron looks ok

  11. This is the same magnetron as is in my UK made Bosch built-in microwave that would cost me big $$$ to replace, so thank you. I heard the buzzing noises and then a blown fuse. Opened up microwave and found a crack in the magnet of the magnetron.

  12. Microwave is a very useful home appliance. Good points on how to rectify the microwave heating issue.We run ConCare Godrej Microwave service centers in Chennai. Microwave heating is a very common issue and experienced person can deal with it quite easily.